Carbon Copy Cloner Overview

[CCC Help] [Browse Help Topics]

System Requirements

• Mac OS 10.4 Tiger (10.4.8 or higher)
• Mac OS 10.5 Leopard
• Mac OS 10.6 Snow Leopard

Supported configurations

• HFS+ formatted partition or hard drive
• Firewire and USB hard drives including iPods*
• CCC will not backup directly to optical media
• CCC is supported only on machines that officially support Mac OS X Tiger (or higher)

Installing Carbon Copy Cloner

Carbon Copy Cloner is distributed via a disk image -- all documentation and required components are contained within the application on this disk image. You may copy CCC to your Applications or Utilities folder, or anywhere else you prefer.

Basic Cloning

In its simplest form, CCC can clone one hard drive to another, copying every single file to create an exact replica of your source hard drive. This is very useful if, for example, your laptop is damaged and you must send it in for repair. Apple recommends that you backup your data before sending it in for repairs because they are not responsible for lost data. With CCC, simply attach an empty Firewire or USB hard drive (external hard drive) to your laptop and clone your entire internal drive to the external hard drive. While your laptop is out for repair, you can boot another system from the external hard drive and continue to use your configuration as if booted from your laptop. When your computer returns from repair, simply restore your external hard drive back to the laptop's internal drive and you're ready to continue on with life. No data lost, not an icon out of place.

Learn more about performing basic clones with Carbon Copy Cloner

Using CCC for general backup

CCC can also be used to perform regular backups of your data. When you select a source volume in CCC, you are presented with the contents of that volume (hidden items too). Simply uncheck the items that you do not want to backup, and CCC will provide ample indication what will and will not be copied. Select a target volume to which you would like to backup, then press the clone button. You have the option to delete items on the target that are not on the source, or simply leave them alone. You also have the option to send your files to another Macintosh on your network. CCC will first scan the source and target volumes for the files to be copied, then will copy only the files that have changed. That's a powerful backup!

Learn more about backing up your data with Carbon Copy Cloner
Learn more about backing up your data to another Macintosh on your network

Scheduling tasks for automated backup

The key to a successful backup plan is to actually do the backups regularly. When left to a human, the task often gets tacked on to the end of a very long list of other things to do. When you eventually have a catastrophe, the data is simply gone. You know that feeling -- you just lost six years of family photos. Your kids being born, their first birthdays, their first everything. The answer to this is consistent and regular backups, placed on a schedule and handled automatically by your computer. CCC includes that functionality, and takes it two steps further.

Backups only work when the computer is awake. If you're a mobile user, the scheduled backup task often does not occur (say your laptop is in a briefcase at the time) or it occurs at an inopportune time, consuming hard drive bandwidth that you simply can't afford. CCC solves this problem by allowing you to defer the scheduled task to a time that you know the computer will be on and idle. If the machine is asleep when the task is scheduled to occur, the task will run upon wake. Bad time? Reschedule to any time, any day.

What happens when your scheduled backup starts but your external hard drive doesn't happen to be attached? Usually you just miss that backup attempt and you wind up playing Russian Roulette with your backup. CCC solves this too. If your backup hard drive is unavailable when the task is scheduled to occur (perhaps you're listening to tunes on your iPod at the time), CCC will immediately run the backup when you reattach your hard drive.

Learn more about scheduling backup tasks with Carbon Copy Cloner

Restoring your data from a backup

Carbon Copy Cloner uses tools built-in to the operating system to back up your data and clone your hard drive. Rather than using proprietary archival methods, CCC backs up your data to an ordinary filesystem that you can browse in the Finder or to a standard disk image like those you download over the Internet. Need to restore a file? Simply browse your backup device and copy the file right in the Finder. If you backed up to a disk image, just mount the disk image and locate the file. If you would like to restore an entire volume, the procedure is exactly the same as it was for creating your original backup: use Carbon Copy Cloner. To restore, simply select your backup as the source and the replacement drive as your new target. CCC also creates bootable backups so you also have a "rescue" drive at hand should something happen to your original.

Learn more about restoring specific files from a backup
Learn more about restoring from a clone
Learn more about restoring from a disk image
Learn more about restoring from a backup stored on another Macintosh on your network

 

Working with FileVault home directories

FileVault protects the contents of your home directory by enclosing it in an encrypted disk image. When you log in, the encrypted disk image is unlocked via your login and password and mounted for use as your home directory. Mounted disk images pose an interesting problem to incremental backup utilities. By simply being mounted and accessed (e.g. via browsing the contents), the content of a disk image, and thus the disk image file itself, is modified. If you run CCC while logged in to a FileVault-protected account, there is a strong chance that the FileVault disk image will be modified while it is being backed up, resulting in a corrupted version of the disk image on your backup volume. Also, because the contents of your FileVault-protected home directory are technically on another volume, CCC will not back up the contents of your home directory when backing up your root filesystem (e.g. your boot drive).

For these reasons, you should either exclude your FileVault disk image file from your backup routine while logged into a FileVault-protected account (and set up a separate routine for backing up the contents of your home directory), or you should only run CCC while logged into an account that is not protected by FileVault.

What settings are right for me?

Carbon Copy Cloner is packed with many different features. To learn what features and options to use for your particular situation, read through the usage scenarios described in the document titled "Usage Scenarios for Carbon Copy Cloner".

Usage Scenarios for Carbon Copy Cloner

 

What does CCC cost?

Carbon Copy Cloner doesn't cost you a dime until you completely trust it. That's the way all backup software should work -- pay when you really feel confident that it's going to do the job that it claims. CCC is "uncrippled" shareware, meaning that all features are available whether you've paid or not. No registration is ever required, but once you trust it, a small donation is appreciated for continued development. Choose "Donate to Bombich Software" from CCC's Help menu to send a donation or use the link below. Thanks!

Note: You may have noticed that there is now a sponsorship banner at the bottom of the cloning status panel while CCC is running. I know what you're thinking, it's an abomination! Right? Well, whenever I post updates to CCC, my bandwidth costs go through the roof. I have chosen to subsidize these costs with banner placements from sponsors that I know and trust. I also introduced the banners as unobtrusively as possible -- in a location and at a time that shouldn't affect your use of CCC.

You can make the banners go away by sending in a donation! Choose "Donate to Bombich Software" from CCC's Help menu, then simply click on the "I paid" button in the Donation dialog and the banners will no longer appear. If you're affiliated with an Education institution, please click on the "I paid" button *without* sending in a donation (seriously).

Donate to Bombich Software

License

View the license for CCC

			Tips for people getting started with Carbon Copy Cloner

[CCC Help] [Browse Help Topics]

• Choosing a backup volume
• Formatting your hard drive for use with Carbon Copy Cloner
• How frequent should my backups be?
• Performance suggestions
• Getting additional help

 

Choosing a backup volume

The goal of backing up your data is to protect yourself from hardware malfunction and accidental or malicious deletions. To effectively protect your data from both of these scenarios, it is best to back up to media that is not physically located inside your Macintosh (e.g. to an external Firewire or USB hard drive, or to another Macintosh), but at minimum to another physical hard drive (e.g. not to another partition on the same hard drive). Additionally, you should choose media that allows you to boot your Macintosh from the backup. A bootable backup gives you not only a really easy way to verify the fidelity of your backup, but it also allows you to instantly regain productivity should catastrophe strike. Rather than spending your morning restoring your OS and data, simply boot from your backup and carry on with your business.

Before you purchase a hard drive for backup, consider the following options:

Internal or external?
If you have a Mac with room for additional internal hard drives, you can use that space for your backup hard drive. I prefer external hard drive enclosures for portability reasons — I can easily swap a pair of external hard drives between office and home to have an inexpensive offsite backup solution. This also gives me the opportunity to easily leverage that hard drive to back up multiple Macs.

USB or Firewire?
Many hard drive enclosures have Firewire, USB, or both interfaces for connecting the hard drive to your computer. Either of these interfaces will work fine for backing up and safeguarding your data, however, PowerPC Macs cannot boot from USB-attached hard drive enclosures. While Intel-based Macs can boot from either, I generally recommend using Firewire for performance reasons. Backups over Firewire are always faster than backups over USB.

Where should I buy it?
Hard drive enclosures are not all built the same, some are not even capable of booting a Macintosh. I prefer to work with vendors that cater to the Macintosh market because I can get assurance that they have tested their products with Apple hardware and Mac OS X. There is a lengthy thread in the CCC support forums on the subject of "What firewire drives have you had success or failure with?" that is worth a read (perhaps starting from the last page, it goes back many years).

 

Formatting your hard drive for use with Carbon Copy Cloner

Mac OS X is installed on an HFS+ filesystem. The HFS+ filesystem defines many types of metadata that describe non-data attributes of your files. Creation date, access control lists, permissions and ownership, Finder flags, and extended attributes are among the various metadata types defined in the HFS+ standard. To adequately back up all of your files and their associated metadata, CCC requires that your backup volume is also formatted as HFS+.

When you purchase a new hard drive, or if you have a hard drive that you use with a Windows computer, that hard drive is often pre-formatted as FAT32. While the hard drive's volume may mount just fine in the Finder, and you are able to access files on the volume, CCC won't let you back up directly to the FAT32 volume because some filesystem metadata would not be transferred. Most notably, you'll lose ownership and permission metadata as well as any Access Control List settings. These types of metadata are very important for maintaining the security of your data and your Mac's operating system.

Additionally, Macintoshes can only boot from hard drives partitioned with either the Apple Partition Map (APM) scheme (PowerPC- or Intel-based Macs) or the GUID Partition Table (GPT) scheme (Intel-based Macs). The hard drive icons that you see in the Finder are volumes. The partition scheme of a hard drive describes how volumes are physically defined on the hard disk. Every hard drive has exactly one partition scheme and at least one volume. When you "partition" a hard drive, you simply create multiple volumes on that hard drive.

Follow these steps to format your hard drive as an HFS+ volume:

1. Launch Disk Utility
2. Click on the hard drive device in the list on the left (the volumes have names that you see in the Finder, like "Macintosh HD" whereas the hard drive device has a name that includes the size of the hard drive and a vendor name or serial number, like "111.8 GB ST9129876A")
3. Click on the Partition tab
4. Choose "1 Partition" from the "Volume Scheme" popup menu (or more if desired).
5. Click on the "Options" button at the bottom of the partitions table and choose a partition scheme appropriate for the way you intend to use the hard drive (APM for PowerPC Macs, GPT for Intel-based Macs), then click the "OK" button:





6. Provide a name for your volume that will allow you to easily identify it as a backup volume.
7. Specify "Mac OS Extended (Journaled)" as the volume format.
8. Click on the "Apply" button

Your new hard drive is now ready to go!

What if I already have a lot of data on the hard drive that I want to use for backup?
If your hard drive already has data on it that you do not want to distrurb, there are a few options that may be available to you:

• Add a new partition to the hard drive

If the hard drive is partitioned with the GPT partition scheme, you can use Disk Utility to resize existing volumes (those volumes must be formatted with a filesystem that supports resizing, such as HFS+) and to add new partitions. These actions can be done non-destructively, as long as the hard drive is partitioned with the GPT partition scheme.

• Back up to a disk image

If you simply cannot reformat or repartition your backup hard drive, you can use CCC to back up your data to a disk image. This subject is covered in the "Using CCC to create disk images" section of the documentation.

• Leverage CCC's "Protect root-level items on the target" feature

If your hard drive is partitioned and formatted correctly and does not already have a version of Mac OS X installed upon it, you can use that hard drive for back up without losing the existing contents. This subject is covered in the "Options to the Incremental backup of selected items method" section of the documentation.

 

How frequent should my backups be?

I find hourly backups to be very intrusive. If I did decide to do hourly backups, I might choose to back up a smaller subset of files (e.g. vs. the entire filesystem) so the backups occur very quickly. Otherwise, I'd just set the system to back up when I'm not using the system. My production machine backs up once a day at 5:30.

Feel free to experiment with the frequency of the backup to see what works best for you. I've decided that the risk of failure on any given day is low enough that I'd rather not have it interfere with my productivity. If an hourly backup were to cause me a minute or two of productivity loss per run (via distraction, having to wait, or generally slowing me down), that would start to add up quickly. Eventually it would outweigh the four hours of work I might lose if one day my drive failed at noon.

 

Performance suggestions

When backing up using the "Incremental backup of selected items" method, you'll notice that CCC will first scan the source volume to build a list of items it should consider for backing up. If you have a particularly high number of files on your source volume, you may want to put some thought into how your files are organized. For example, if you have a large number of files that never change (perhaps some old, completed projects), you can collect these into a folder named "Archives", back it up once, then exclude it from future backups. CCC will not delete excluded items from your target volume, so as long as you keep the original on your source volume, you will always have two copies of your archived content. Because these items are excluded from your daily backups, CCC will not spend time or RAM enumerating through those files for changes.

 

Getting additional help

When you encounter a problem, need clarification, or are unsure what to do, you should consult the online help to see if your question is answered there. In particular, check out the Frequently Asked Questions section. If you don't find what you need in the online help, visit the Bombich Software forums and search for answers there. The forums are our primary avenue of providing support -- they best allow us to provide one-to-many help, build a knowledge base, and identify trends of usage and problems. If you are unable to get the help you need in the forums, or if you have identified a reproducible error condition, submit a problem report via CCC's Help menu. When you submit a problem report, the developers at Bombich Software will attempt to reproduce the problem and find a resolution. If further clarification is required, we will contact you via email.

			What can I do with Carbon Copy Cloner?

[CCC Help] [Browse Help Topics]

I want to clone my entire hard drive to a new hard drive or a new machine
I want to backup my important data or synchronize my backup drive to my boot drive
I want to backup my important data to another computer on my network
I want to backup multiple machines to the same hard drive, each to its own disk image on the drive
I want my backup task to run automatically on a scheduled basis

 

I want to clone my entire hard drive to a new hard drive or a new machine

There are many different reasons to make an exact clone of your hard drive. Suppose your laptop is damaged and you must send it in for repair. In the meantime, you not only have to borrow another computer for the duration of the repair, you also don't have your data, applications and work environment exactly as they were on your machine. This lack of organization can be very frustrating and inhibit your productivity. When you get your machine back from repair, you have to deal with locating any modified documents on your loaner computer and copying them to your original computer. Also, Apple recommends that you backup your data before sending in a machine for repairs because they are not responsible for lost data.

In this situation, it would be ideal to simply copy off the entire contents of your hard drive to an external hard drive -- to create a "bootable clone" of your production machine. You can then boot a loaner machine from this bootable clone and work from it as if working from your original machine.*

Another common scenario appropriate for cloning is when you have purchased a new computer and you would like to move the entire installation to your new machine. In the past, using CCC for this type of procedure was usually fine. There were and are caveats**, but usually this went quite well. With Apple's transition to the Intel processor, however, it is very common for people to want to migrate from an older PowerPC-based machine to a new Intel-based machine. The version of Mac OS X Tiger that is available for PowerPC machines, however, will not boot the new Intel-based Macintoshes. Therefore, you are encouraged to use the built-in Migration Assistant as prompted when you first boot your new computer. If you are migrating a PowerPC machine to a PowerPC machine, or migrating an Intel-based machine to an Intel-based machine, then, respecting caveats listed below, a basic clone is an ideal way to migrate from one machine to another.

When you need a complete, simple backup of your entire hard drive, use Carbon Copy Cloner's "Backup everything" option.

Learn more about using the "Backup everything" option

 

I want to backup my important data or synchronize my backup drive to my boot drive

While a complete and bootable clone of your hard drive can be very useful in case of emergencies, it is often desirable to maintain a more frequently updated backup of your most important data in multiple locations. In general, it is wise to always maintain at least three copies of the data that is most important to you: the original, a nearby backup, and an "offsite" backup -- something that is kept outside of your home or office in case something terrible happened where you regularly use your computer. Carbon Copy Cloner 3 has been enhanced to provide additional functionality for facilitating this type of backup plan.

You may also notice that cloning your entire hard drive every time you back up your data takes a lot longer than it should. Why not just copy the items that have changed since the last backup? This functionality is a standard feature of Carbon Copy Cloner 3.

When you want to copy a selection of data from your hard drive, use CCC's "Incremental backup of selected items" option. Likewise, if you want to only copy the items that have changed since a previous backup, use CCC's "Incremental backup of selected items" option.

Learn more about using the "Incremental backup of selected items" option

 

I want to backup my important data to another Macintosh on my network

Storing your backup on a locally attached hard drive certainly offers speed and space benefits, but if you'd like to store the backups for one or several machines in a central location, or even offsite, then being able to directly backup to another Macintosh on your network is paramount.

Carbon Copy Cloner 3 offers the option of securely copying your selected data to another Macintosh on your network (or anywhere on the Internet for that matter). After a brief setup procedure to establish trust between your machine and the target machine, simply indicate the IP address or hostname of the machine to which you have access and CCC will take care of the rest.

When you want to copy a selection of data from your hard drive to or from a remote Macintosh, use CCC's "Incremental backup of selected items" option, and choose the "Remote Machine..." option from the Target menu. Likewise, if you want to only copy the items that have changed since a previous backup, use CCC's "Incremental backup of selected items" option.

Learn more about backing up your data to another Macintosh over a network

 

I want to backup multiple machines to the same hard drive, each to its own disk image on the drive

Sometimes backing up your data to a single external hard drive is just too messy and difficult to organize. Suppose, for example, that you have three computers in your household, and everyone backs up to the same external hard drive. Where do you put each person's backup? The single hard drive can't maintain multiple operating systems, Mac OS X does not support that. You could split the drive into three partitions, but that isn't very flexible at all. You could clone each person's drive to a folder on the drive, but that's a little difficult to restore from.

A very good solution in a scenario such as this is to use disk images as the medium of your backup. A disk image is a single file residing on your hard drive that contains the entire contents of another hard drive (except for the free space). When you want to access the contents of that filesystem, you double-click on the disk image to mount the disk image as if it were an external drive attached to the machine. Carbon Copy Cloner 3 leverages disk images to provide you the flexibility of storing several complete, bootable*** backups on a single shared external hard drive. (*** Disk images themselves are not bootable, but you can mount them and restore their content to a physical hard drive to produce a bootable, exact replica of the original).

When you want to copy the entire contents or a selection of data from your hard drive to a disk image, select "New disk image..." or "Choose disk image..." from the target menu. If you want to restore a drive from a disk image backup, boot from a drive other than the target, select "Restore from disk image..." from the source menu and locate the disk image. Choose the drive to which you would like to restore from the target menu.

Learn more about backing up to and restoring from disk images

 

I want my backup task to run automatically on a scheduled basis

It takes a person of strong resolution to manually back up data frequently enough to prevent a catastrophic loss. For the rest of us, there's task scheduling. Carbon Copy Cloner offers hourly, daily, weekly, and monthly scheduling. If your workstyle is too hectic for scheduling, you can also schedule a task to run whenever your backup hard drive is attached to your computer.

To schedule a backup task, first configure CCC as if you were going to run a backup task immediately. Instead of clicking on the Clone button, click on the "Save Task" button. In the Scheduler window that appears, provide a name for the scheduled task and indicate when you want the task to run.

Learn more about scheduling backup tasks with Carbon Copy Cloner

			Using Carbon Copy Cloner to backup selected items on your computer and to synchronize disks

[CCC Help] [Browse Help Topics]

When you want to copy a selection of files to another drive or disk image, you use the "Incremental backup of selected items" option in CCC. This is a really easy way to make a backup of just the files that are important to you, which can be particularly important if your target drive is tight on space. This option also offers a speed advantage -- only the files that have changed will be copied to the target drive. For day to day incremental backups, this is the ideal method for backing up your data and your boot volume.

Configuring what items should be copied (or not)

When you choose a disk in the source menu, and the "Incremental backup of selected items" option is selected, the "Items to be copied" table populates with the contents of that volume. Each file and folder has a checkbox next to it -- unchecking a checkbox indicates that you do not want that item copied to your backup drive. You will also notice that each folder has a disclosure triangle, just like in the Finder. Click on the disclosure triangle to reveal the contents of a folder, then you can continue deselecting items to be copied, if desired. CCC will not allow you to navigate beyond the folders for which you have permission to view. Additionally, if you deselect an item that is required for Mac OS X to boot, CCC will indicate that the target volume will not be bootable. Your target volume will be bootable as long as it meets the bootability requirements and you select to copy all required system files.

Bootability verification

CCC determines whether your target volume will be bootable and indicates this beneath the "Cloning Options" section. To qualify as "bootable", the following requirements must be met:

• The target volume cannot be a disk image -- you cannot boot your Macintosh from a disk image.
• The source and target volumes must be local volumes -- CCC cannot determine the bootability of a remote volume.
• If the Macintosh is a PowerPC Macintosh, the target device must be an internal volume or on a Firewire hard drive. Intel Macintoshes can boot from either an internal volume, a Firewire hard drive, or a USB hard drive.
• The files and folders required by Mac OS X must be present on the source volume. These include: /Library, /System, /Users, /bin, /etc, /mach_kernel, /private, /sbin, /tmp, /usr, and /var.
• The files and folders that are required by Mac OS X must be selected to be copied to the target volume (applicable only to the "Incremental backup of selected items" cloning method).
• If the Macintosh is a PowerPC-based Macintosh, the hard drive on which the target resides must be partitioned using the APM (Apple Partition Map) partitioning scheme. Intel-based Macintoshes ship with hard drives formatted with the GPT (GUID Partition Table) format, and will not boot a PowerPC Macintosh.
• If the Macintosh is an Intel-based Macintosh, the hard drive on which the target resides must be partitioned using the Apple Partition Map or GUID Partition Table partitioning scheme. You may have difficulty booting or running an Intel-based Macintosh from a hard drive formatted with the MBR (Master Boot Record) partitioning scheme.

What is the "Gear" menu for?

The popup menu next to the source menu that has a gear icon is a contextual filters menu. That menu is enabled when you have selected a local volume or disk image in the source menu. In short, filters are created automatically for you when you deselect items in the "Items to be copied" table. You can edit filters and save customized filters for future use, as well as add file type filters and custom rules. Filters are explained in more detail in this section of CCC Help.

Options to the "Incremental backup of selected items" method

"Delete files that don't exist on the source"

By default, the "Incremental backup of selected items" method will copy the selected items to your target drive, copying only the items that have changed and leaving in place any files on the target that do not exist on the source. Essentially, the two drives are merged onto the target. Often when you back up your data, however, you also want to delete items on the backup that have been deleted on your source hard drive. Select the "Delete files that don't exist on the source" option if you would like items that have been deleted on the source to be deleted from the target.

 

"Protect root-level target items"

Not everyone has a hard drive that can be completely dedicated to the task of backing up a single volume. If you have content on your backup volume that you do not want deleted, yet you want to keep your backup "clean", use the "Protect root-level target items" option. For example, suppose you have these items on your source volume:

Applications
Library
System
Tax Records (This year)
Users

And you have these items on the target volume:

Documents
Older Tax Records
Photos 1976-2001
Tax Records (This year)

With the "Incremental backup of selected items" method plus the "Delete files that don't exist on the source" option, the Documents, Photos 1976-2001, and Older Tax Records directories would be erased completely (bad!*), and the Tax Records (This year) directory would be updated to exactly match the Tax Records (This year) directory on the source (probably a good thing). By adding the "Protect root-level target items" option, the Documents, Older Tax Records and Photos 1976-2001 directories are left untouched because they are unique to the target volume. The Tax Records (This year) directory, however, is still updated to match the Tax Records (This year) directory on the source. When your goal is to keep an up to date backup without older cruft, that's an ideal scenario.

* Granted, they should be backed up at least one other place if they are important, right?

"Archive modified and deleted items"

In the event that you accidentally delete a file and don't notice until after your scheduled backup has occurred, you are typically out of luck -- the file is deleted from your backup (when using the "Delete items that don't exist on the source" option). With the "Archive modified and deleted items" option, deleted items are not deleted from the backup, rather they are moved to a time-stamped folder at the root level of your backup volume (e.g. "_CCC_2009_September_06_17-30-00"). Should you ever need to recover a long-ago deleted file, or simply the version of a file before last week's major revision, simply navigate to the root level of your backup volume and find the folder named with the date that the backup occurred.

 

What happens to data already on the target drive?

If you already have data on your target drive, the "Incremental backup of selected items" method will only delete those items if:

1. You have selected the "Delete files that don't exist on the source" option and
2. The file does not exist on the source

If a file exists on the source and target at the same path (e.g. /Users/bob/Desktop/file.txt and /Volumes/Backup/Users/bob/Desktop/file.txt), then the file on the target volume will be overwritten if it is older than the file on the source. Otherwise it will be left untouched.

Additionally, directories whose names begin with _CCC on the target will never be deleted while using the "Incremental backup of selected items" cloning method. These items will only be deleted if you have selected the "Delete files that don't exist on the source" option and you're using the "Backup everything" cloning method. Special handling of items at the root level of the target volume are described in the "Protect root-level target items" section above.

 

How do I restore files backed up using the "Incremental backup of selected items" method?

If you need to restore just a file or handful of files, simply browse the backup drive in the Finder and copy those items back to your original drive to restore them. If you need to restore many files using CCC, select the drive that you backed up to as the source, select your original drive as the target, then proceed as you did when you originally backed up your drive. Carefully consider the "Delete files that don't exist on the source" option; if there are other important files on the volume you're restoring to, you don't want to accidentally erase them. Also, you may deselect the root of a volume in the "Items to be copied" table, then re-select only a few items to limit what items are restored. Note that you cannot select the boot drive as the target, you will need to boot from another drive if you need to restore directly to your boot drive.

What else can I do with the "Incremental backup of selected items" method?

In addition to backing up your data or synchronizing one volume to another, CCC also allows you to back up selected files to a disk image and to back up selected files to another computer on your network.

Learn more about backing up to disk image
Learn more about backing up to a subfolder on a hard drive
Learn more about backing up to a remote host

			Using Carbon Copy Cloner to create an exact clone of your hard drive

[CCC Help] [Browse Help Topics]

Carbon Copy Cloner's most basic and revered task is to create a "carbon copy" bootable clone of a hard drive. CCC 3 takes this to a new level with Apple Software Restore, a low-level tool developed by Apple and built-in to Mac OS X. Apple Software Restore is the most highly regarded tool for performing disk to disk clones, and Carbon Copy Cloner brings all the functionality and more to your desktop. To clone a hard drive using Carbon Copy Cloner, use the "Backup everything" method listed under Cloning options:

The "Backup everything" method will attempt a block-level clone of your source volume if you have indicated to "Delete items from the target that don't exist on the source". If you have not selected that option, or if a block-level clone cannot proceed (see below), this cloning method will perform a file-level copy of everything on the source volume to the target volume. If the target volume already contains some of the content of the source volume (e.g. from a previous backup), that content will be efficiently updated. The end result in both cases is an exact, bootable backup of your source volume.

Options to the "Backup everything" method

This cloning method has one option: Whether to delete items from the target that don't exist on the source prior to cloning. This option is important to consider when your goal is to create a bootable clone -- read the gray box at the bottom to understand how this option affects your clone.

 

Block-level copies vs. file-level copies

Cloning an entire hard drive to another drive can be achieved in two ways: 1) Copying every file individually from one volume to the other or 2) Copying the underlying blocks from one hard drive to the other. These two methods are called "file-level copying" and "block-level copying", respectively. While each method produces functionally the same result, block-level copying is almost always significantly faster than file-level copying, and is therefore the preferred method for disk to disk clones.

 

To benefit from a block-level copy, the following criteria must be met:

1. You must choose to "Delete items from the target that don't exist on the source" during the clone.
2. You must be able to unmount both devices (there cannot be any open files on either drive and you cannot be booted from either drive). Do not actually unmount the drives prior to the clone.
3. The target drive must be at least as large as the source drive.

 

If any of these criteria are not met, CCC will automatically fall back to a file-level clone. A file-level clone will yield the same result -- a bootable clone (assuming you didn't merge two operating systems), but it will take a little longer.

While a block-level clone is rarely required to insure the fidelity of your backup, some people find comfort in the fact that, block-for-block, the resulting target is precisely like the original (this is simply impossible with a file-level clone). When possible, CCC will always prefer a block-level clone. However, don't lose sleep if meeting the requirements for a block-level clone is untenable for your particular backup or cloning situation. The file-level backup engine in CCC has been tuned and honed to bring the best performance and fidelity possible among Mac OS X backup utilities.

Do I need to clone, or just backup?

Often people clone when all they really need is a backup. When you clone a volume, every file is copied, and this can take a fair amount of time. If you just recently backed up your entire drive, use the "Incremental backup of selected items" method to backup your data instead. That method copies only the items that have changed, thus your backup is much faster. If you're moving to a new hard drive, cloning your machine prior to repair, etc. then the cloning method is the right choice for you.

Bootability verification

CCC determines whether your target volume will be bootable and indicates this beneath the "Cloning Options" section. To qualify as "bootable", the following requirements must be met:

• The target volume cannot be a disk image -- you cannot boot your Macintosh from a disk image.
• The source and target volumes must be local volumes -- CCC cannot determine the bootability of a remote volume.
• If the Macintosh is a PowerPC Macintosh, the target device must be an internal volume or on a Firewire hard drive. Intel Macintoshes can boot from either an internal volume, a Firewire hard drive, or a USB hard drive.
• The files and folders required by Mac OS X must be present on the source volume. These include: /Library, /System, /bin, /etc, /mach_kernel, /private, /sbin, /tmp, /usr, and /var.
• The files and folders that are required by Mac OS X must be selected to be copied to the target volume (applicable only to the "Incremental backup of selected items" cloning method).
• If the Macintosh is a PowerPC Macintosh, the hard drive on which the target resides must be partitioned using the Apple Partition Map. Intel-based Macintoshes ship with hard drives formatted with the GPT (GUID Partition Table) format, and will not boot a PowerPC Macintosh.

What else can I do with the "Backup everything" method?

In addition to cloning one volume to another, CCC also allows you to clone a volume to a disk image.

Learn more about cloning to disk image

 

How do I restore files backed up using the "Backup everything" method?

If you need to restore just a file or handful of files, simply browse the backup drive in the Finder and copy those items back to your original drive to restore them. If you need to restore a larger subset of files, but not the entire volume, click here to learn how to restore files with the "Incremental backup of selected items" option.

To restore an entire volume, for example your boot volume after a disk failure, you will need to boot from an external Firewire or USB hard drive. Ideally, you will simply boot from the external hard drive that you backed up to using CCC. Launch CCC, select the drive that you backed up to as the source, select your original (or replacement) drive as the target, choose to "Backup everything", then clone. If the target drive must be bootable, you must use the "Delete items from the target that don't exist on the source" option (see below for the explanation).

			Using Carbon Copy Cloner to backup to and restore from disk images

[CCC Help] [Browse Help Topics]

Sometimes backing up your data to a single external hard drive is just too messy and difficult to organize. Suppose, for example, that you have three computers in your household, and everyone backs up to the same external hard drive. Where do you put each person's backup? The single hard drive can't maintain multiple operating systems, Mac OS X does not support that. You could split the drive into three partitions, but that isn't very flexible at all. You could clone each person's drive to a folder on the drive, but that's a little difficult to restore from.

A very good solution in a scenario such as this is to use disk images as the medium of your backup. A disk image is a single file residing on your hard drive that contains the entire contents of another hard drive (except for the free space). When you want to access the contents of that filesystem, you double-click on the disk image to mount the disk image as if it were an external drive attached to the machine. Carbon Copy Cloner 3 leverages disk images to provide you the flexibility of storing several complete, bootable* backups on a single shared external hard drive. (* Disk images themselves are not bootable, but you can mount them and restore their content to a physical hard drive to produce a bootable, exact replica of the original).

Backing up to a new disk image

After choosing a source volume from the Source Disk popup menu, choose "New disk image..." from the Target Disk popup menu. Provide a name and choose a location to save your disk image. If you plan to back up to this disk image again in the future, select the option to "Create a read/write sparse disk image". If you want a read-only disk image for archival purposes, choose the option to "Create a read-only disk image". Note that if you schedule a task in which you create a new image, CCC will recreate the image every time the task runs. See the Backing up to an existing (read/write) disk image section below for a more appropriate choice for scheduling backups to a disk image.

Read/write "sparse" disk images
A sparse disk image is a type of read/write disk image that grows as you copy files to it. In general, sparse disk images only consume as much space as the files they contain consume on disk, making this an ideal format for storing backups.

Read-only disk images
When creating a read-only disk image, you have two additional options. If your target disk is short on space, you can compress the disk image. Compression rates vary on the content of your source, but you can typically expect to reduce the size of your disk image by about half when using compression. There is a subtle behavior that you should take note of when considering this option as a space-saving measure: When using the "Incremental backup of selected items" cloning method, CCC will first create a read/write disk image, copy the selected items to it, then convert the disk image to read-only compressed. In this case, you will actually need twice the space on your target as the items to be copied consume on the source. When using the "Backup everything" cloning method, this limitation does not apply, CCC will create a read-only compressed disk image in one step.

The second option allows you to segment the disk image. This option is ideal if, for example, you intend to burn the segments to optical media.* Like with the compression option, CCC will also create a temporary read-write disk image -- not segmented -- when using the "Incremental backup of selected items" cloning method.

* To mount a segmented disk image, all segments must be present on the same media. Burning disk image segments to optical media is a great archival practice, just keep in mind that should you ever need to restore from that backup, you will first need to copy all segments onto a volume with adequate capacity.

Encrypting disk images
If any of the data that you are backing up is sensitive, and if your backup device may be in an insecure location, it is a good idea to enable encryption when backing up to a disk image. CCC uses 128 bit AES encryption to encrypt disk images. Note: CCC does not currently support encryption during scheduled tasks.

 

Backing up to an existing (read/write) disk image

If you regularly make backups to a disk image, this is the option you will want to choose when choosing a target disk. After choosing a source volume from the Source Disk popup menu, choose "Choose disk image..." from the Target Disk popup menu. In the Open dialog box, navigate to and select your disk image and click the OK button. After clicking on the Clone button, CCC will mount the disk image and backup your data as if it were any other backup device.

When backing up to an existing disk image, be sure to choose a disk image that is writable. If you choose a sparse disk image that CCC created in a previous backup, CCC can be configured to copy everything again, overwriting data on the disk image, or to copy only the items that have changed. A sparse image will grow as data is copied to it.

Learn more about performing basic clones with Carbon Copy Cloner
Learn more about backing up your data with Carbon Copy Cloner

 

Restoring from a disk image

To restore files or an entire filesystem from a disk image, simply select "Restore from disk image" from the Source Disk popup menu and locate your backup disk image. CCC will mount the disk image and you may then proceed with the restore procedure using either the "Incremental backup of selected items" or "Backup everything" cloning method. If you want to restore your disk image to your boot volume, or if you need to restore a disk image and you do not have a bootable volume available, you can boot from your Mac OS X Installer DVD and use Disk Utility to restore the disk image:

1. Reboot your computer from the Mac OS X Installer DVD
2. After the Installer application loads, choose "Disk Utility" from the Utilities menu
3. From the File menu, choose "Open Disk Image..." and locate the disk image that you would like to restore
4. In the list in the pane on the left, click on the mounted disk image's volume
5. Click on the "Restore" tab on the right side of the window
6. Drag the mounted disk image to the Source field
7. Drag the hard drive that you would like to restore to into the "Destination" field
8. Check the box to erase the destination, then click on the Restore button.

			Using Carbon Copy Cloner to backup to another Macintosh on your network

[CCC Help] [Browse Help Topics]

Carbon Copy Cloner 3 offers the option of securely copying your selected data to another Macintosh on your network (or anywhere on the Internet for that matter). After a brief setup procedure to establish trust between your machine and the target machine, simply indicate the IP address or hostname of the machine to which you have access and CCC will take care of the rest. Note: Backing up to a remote Macintosh is not the same as backing up to a network filesystem. Read this section of the documentation for more information on the latter scenario.

To successfully set up CCC to back up to a remote Macintosh, you will be required to:

1. Enable Remote Login on the remote Macintosh
2. Determine the Unix path to the folder on that machine that you would like to back up to
3. Install an "Authentication Credentials" package on your local machine (CCC will place this package on your Desktop)
4. Transfer that same "Authentication Credentials" package to your remote Macintosh and install it there
5. Verify that the system time on each Macintosh is reasonably in sync with the other
6. Confirm that the backup device on the remote Macintosh is ready and mounted (CCC does not currently perform this verification).

Configuring CCC to back up to a remote Macintosh is an advanced configuration scenario. If you are unsure of any of these settings, please seek advice at the Bombich Software Forums before proceeding.

Enabling Remote Login on the remote Macintosh

To enable Remote Login on your remote Macintosh, log in to that machine as an admin user and launch System Preferences. Open the Sharing Preference Pane and check the box next to "Remote Login". If you are running Mac OS 10.5 Leopard or greater, be sure to allow access to "All users", or explicitly add the "System Administrator" user to the list of restricted users. Take note of the message at the bottom of the window, e.g. "To log in to this computer remotely, type "ssh username@yourhost.yourdomain.com" at a shell command prompt." The text after the "@" symbol is the hostname or IP address that you will provide in CCC's "Remote Macintosh" dialog box.

Determining the "Path to backup directory"

To determine the value to enter in this field, first log in to the remote Macintosh as an admin user and create the destination folder. Click on the destination folder, then from the Finder's "File" menu, choose "Get Info". In the "General" section of the Get Info panel, the "Where" attribute indicates where that folder is located. The path to your backup directory will consist of that location, plus "/", plus the name of your destination directory. For example, I just created a folder named "Mike-Backups" in the Shared directory on my remote Macintosh. The Get Info panel indicates that it is located at "/Users/Shared", therefore the path to my backup directory is "/Users/Shared/Mike-Backups". Note: while spaces and special characters should not pose a problem in the backup directory path, I strongly recommend that you avoid them.

The "Authentication Credentials" package installer

Before you can back up to a remote Macintosh, you must first set up "public key authentication" (PKA) between the Macintosh that you're running Carbon Copy Cloner on and the Macintosh that you'd like to back up to. With PKA, you don't need to provide a username/password to access the remote machine. Instead, CCC uses pre-shared, 128-bit key pairs to identify the source and target machines. When you click on the button to create an Authentication Credentials installer, CCC will generate this key pair and create a package installer. The "Authentication Credentials Installer" installs the key pair into the root account on your machine and then into the root account on the target machine. You must install them in this order.

Note that you are NOT required to enable the root account on either machine. This is avoided by using public key authentication instead of password-based authentication.

Remote machine requirements

At this time, CCC requires the use of the root account (does not have to be enabled) on both the source and target machines. To successfully back up to a remote machine, you must have administrative privileges on both machines. This may be improved upon in a future release.

CCC also requires that the remote machine be running Mac OS 10.4.8 or later. The ability to back up to non-Mac OS X machines may be improved upon in a future release.

CCC does not currently support backing up directly to an AFP, NFS, or SMB network share. You can back up to a disk image on these types of volumes, but a volume to volume clone is not permitted (or technically feasible) to network shares. Read this section of the CCC documentation for more details on this topic.

Additional pointers for advanced users

Carbon Copy Cloner's public key-based authentication is designed to work with no additional configuration of the services required for backing up over a network connection. CCC uses rsync over an ssh tunnel (port 22 by default) to perform the backup. If you do make modifications to the sshd configuration, consider how that may affect your backup. For example, CCC requires use of the root account over ssh. If you set the "PermitRootLogin" key in the sshd.conf file to "no", you will not be able to use CCC to or from that machine. It's an important distinction to note that the root account does not have to be *enabled*, but sshd must permit the use of the root account.

 

Restoring from a backup on a remote machine

The restore procedure is nearly identical to the backup procedure. Launch CCC, then select "Remote Macintosh..." from the source menu. In most cases, the Remote Settings dialog will be populated with the same information you used to back up originally. Select a target volume, then click the Clone button. Carefully consider the "Delete files that don't exist on the source" option; if there are other important files on the volume you're restoring to, you don't want to accidentally erase them. Also, when restoring from a remote Macintosh, you will not be given the choice of what files to restore, it's all or nothing. Note that you cannot select the boot drive as the target, you will need to boot from another drive if you need to restore directly to your boot drive.

 

Managing backups of multiple computers to one "backup server"

Carbon Copy Cloner can be used to back up several Macs to one particular Mac on your network. When you have several machines in your home or office that are turned on and awake at predictable times of the day, this can be a good method of reducing the number of hard drives that you use for backup, and can also help you establish offsite backup practices by consolidating your data. I use this strategy myself, so I'll describe my setup further.

I have a G5 that stays on all the time (media server, file server, backup server, and runs my network). I have two hard drives attached to it, "Backup" and "Offsite Backup." The "Backup" hard drive is a staging hard drive -- it has a folder at the root level for each computer that I back up (five total). When I originally set up the backup task on my laptop, for example, I configured the remote Macintosh information as:

IP address: 10.0.1.11
Path: /Volumes/Backup/Mike

Ditto for the other four machines, but to their respective folders. Each of these machines is scheduled to back up to the "Backup" volume on a nightly or bi-nightly basis, and the backup server is then configured to clone "Backup" to "Offsite backup" once a night (actually very early in the morning) after all those other tasks have completed. Every other week my wife takes the "Offsite Backup" hard drive to work and brings home the one from work. This has been working solidly for me for over a year, and I've had a couple occasions where I've actually needed to retrieve data from the backup (so I know it's really working!).

There are advantages and disadvantages to backing up to a folder on a remote volume (e.g. "Backup"). The main advantage is that I don't have to make a guess at how much space to allocate to partitions for each of the computers I back up. There's one partition, and when space is tight I simply erase some of the archive folders or buy a larger hard drive.

I can't, however, boot from that hard drive because all the OSes are in sub folders. This is no big deal for me because I have plenty of bootable devices laying around. If I didn't, then I would probably partition the "Backup" hard drive and configure each machine to back up directly to one of the partitions, e.g.:

IP address: 10.0.1.11
Path: /Volumes/Backup_Mike <-- root of the "Backup_Mike" partition

That partition will be bootable if you back up your entire hard drive to it (e.g. both the OS and your user data) and if the disk is partitioned with a partitioning scheme that the machine you're trying to boot supports. The bonus to this method is that you can get back to productivity very quickly should you have some sort of disk failure.

The Intel vs. PPC partitioning issue certainly does complicate matters -- if you have a mix of Intel and PPC Macs, you're likely going to need separate bootable volumes for these machines. If I were in this situation, I would probably have two backup hard drives -- one partitioned as APM for the PPC Macs, and another partitioned as GPT for the Intel Macs -- then each drive sliced into however many volumes you need for backing up your computers. Alternatively, you could do as I have -- maintain separate boot drives (e.g. with a base installation of Mac OS X) for Intel and PowerPC Macs, then have another hard drive or partition with folders that are kept up to date with each machine you want to back up.

 

A caveat for backing up to a remote Macintosh that has no user logged in

For "improved detachability", Mac OS X will unmount any non-internal volumes that are attached to the system when you log out. So, for example, if you log out of your computer while a USB or Firewire hard drives is attached, you can detach those hard drives from the system without having to manually unmount them first. This is a good thing -- it would be annoying if you had to log back in to your system just to eject a drive. The downside of this, though, is that if you have a scheduled backup task that runs when no user is logged in, the target volume may be unavailable. For a local backup, CCC will attempt to manually mount the target volume. When the target of your backup task is a remote Macintosh, though, CCC will not be able to mount that volume prior to backing up.

If you anticipate backing up to a remote Macintosh that may be sitting at the loginwindow, you can change the behavior of Mac OS X to not unmount detachable volumes. To change this behavior, run this command in the Terminal application on the remote machine:

sudo defaults write /Library/Preferences/SystemConfiguration/autodiskmount AutomountDisksWithoutUserLogin -bool YES

			Configuring filters in CCC to limit what is backed up

[CCC Help] [Browse Help Topics]

Typically when you clone your hard drive to another drive, you want to copy everything. When you perform regular incremental backups, however, space becomes an issue. Filters allow you to specify what items on your hard drive should not be copied to the backup device when using the "Incremental backup of selected items" cloning method. A filter is created automatically for you when you uncheck items in the "Items to be copied" table. More advanced filtering options are available as well, including the ability to exclude items based on file type and the ability to specify your own rsync-compatible rules.

Creating filters

Creating your own filters is a breeze. Simply choose a source volume in the Source Disk popup menu, then start deselecting items that you do not want to copy. As you deselect items, the default filter for that volume is updated with your selections. To view and edit the filters that you have created, click on the "gear" popup menu next to the Source Disk popup menu. [If this button is disabled, select a source volume from the Source Disk popup menu.]

In the Filter Settings window, you see a list of filters on the left and the contents of those filters on the right. Every time you choose a volume from the Source Disk popup menu, a filter is created for you with a name in the form of "Source Disk (Default)". As you deselect items to be copied, those items are added to the filter. When you quit CCC, the filters are saved and available the next time you launch CCC. Whenever you choose a volume in the Source Disk popup menu in the future, the settings from the default filter for that volume will be applied.

Customizing filters

Typically you will not need to manually configure your filters. If you would like to maintain more than one filter for a particular volume, or if you would like to apply more advanced settings such as file type filters, then you do so in the Filter Settings window. To create a new filter, click the "+" button and provide a name for the filter. To remove a filter, select the filter in the Filters table and click on the "-" button. If you delete a default filter for a volume, that filter will be recreated the next time you select that volume in the Source Disk popup menu.

To delete items from a filter, select the item(s) from the "Items you have excluded..." table on the right and click the "-" button or press the delete key.

Advanced filter options

If the files you want to exclude are scattered across your filesystem, it may be tedious to manually exclude each of them. To address this, CCC implements file type filters. File type filters allow you to specify a file extension (e.g. "dmg", "doc", "mp3", etc.) of a file type that you would like to exclude. Suppose you want to exclude disk images from being backed up, for example*, simply add "dmg" to the File types filter table and any file with that extension will be excluded.

For the truly adventurous, CCC permits the definition of custom rules. These custom rules follow the syntax defined in the rsync man page. Using the rules in the screenshot above as an example:

- Library/Caches
- /var/log
- /Library/Logs

The "No logs or cache" filter will exclude any item that contains "Library/Caches" *anywhere* in the path (for example, ~/Library/Caches in every users home directory as well as in /Library/Caches). Items in the /var/log folder at the root of the volume will be excluded as well as items in /Library/Logs (but not, for example, in /Users/mike/Library/Logs).

You can learn more about custom rules by reading the "EXCLUDE PATTERNS" section of the rsync man page.

Note: Filters specified in the "Advanced options" section of the Filter Settings window will not be reflected in the "Items to be copied" table in the main window.

Suggested additions to your custom filters

As indicated above, read/write disk image files should excluded from an incremental backup regimen unless they are infrequently used. By examining many months of backups, I have discovered that the following "disposable"items also consume too much space on my backup hard drive:

• ~/Library/Caches
• /Library/Logs
• /var/log

 

Items automatically ignored

When copying files using the "Incremental backup of selected items" cloning method, CCC automatically ignores certain files and folders from the backup procedure. The contents of this list were determined based on Apple recommendations and years of experience. The following is a list of the items that are excluded. This list is not configurable (though the curious would eventually learn that these are defined in Carbon Copy Cloner.app/Contents/Resources/defaults.plist).

• .HFS+ Private Directory Data*
• .Spotlight-V100
• /.fseventsd
• /.hotfiles.btree
• /.vol/*
• /Auth.bak
• /Backups.backupdb
• /Cleanup At Startup
• /TheVolumeSettingsFolder
• Trash
• .Trash
• .Trashes
• /TheFindByContentFolder
• /Shutdown Check
• Temporary Items
• /VM Storage
• /OpenFolderListDF
• /Desktop (Mac OS 9)
• /.com.apple.NetBootX
• /Volumes/*
• .VolumeIcon.icns
• /dev/*
• /automount
• /Network
• /private/var/vm/*
• /private/tmp/*
• /.journal
• /.journal_info_block

			Scheduling backup tasks in Carbon Copy Cloner

[CCC Help] [Browse Help Topics]

Carbon Copy Cloner offers hourly, daily, weekly, and monthly scheduling. If your workstyle is too hectic for scheduling, you can also schedule a task to run whenever your backup hard drive is attached to your computer. To schedule a backup task, first configure CCC as if you were going to run a backup task immediately. Instead of clicking on the Clone button, click on the "Save Task" button. In the Scheduler window that appears, provide a name for the scheduled task (double-click "Untitled") and indicate when you want the task to run.

Scheduling a task

To schedule a task, choose the desired repetition interval from the popup menu next to "Run this task:". If you would rather have the backup task run only when the target volume is reattached to your computer, choose "When target is reconnected".

Next choose how many (hours, days, weeks, or months) you would like to skip between backup events ("Repeat every:"). Finally, indicate the time of day at which you would like the event to start. When scheduling a task to run on a weekly basis, you may also indicate what days of the week on which your task should run. At the bottom of the scheduler window, CCC will indicate how frequently the task will run and when it is next scheduled to run.

Additional Settings

By default, CCC uses the name and Universally Unique Identifier (UUID) of your source and target to identify those volumes. By verifying both of these identifiers, there is less risk in, for example, backing up to a volume that has the same name as your usual target but is not actually the target. While beneficial, this behavior can sometimes have the wrong result. For example, if you rotate between a pair of external hard drives, even though they have the same name (e.g. "Offsite Backup"), CCC will not, by default, backup to both of them, it will claim that the UUID of one of the drives does not match that of the originally chosen target.

The deal with this scenario, CCC allows you to disable verification of the target drive's UUID. When deselecting this option, be vigilant that you do not rename your target hard drive and that you never attach a hard drive to your machine that is named the same as your target hard drive.

In addition to disabling the UUID verification, CCC will also allow you to disable verification of the target volume's name. Obviously, both of these options may not be disabled at the same time (CCC won't let you do that), but in cases where you may want to rename your target hard drive, this option will allow you to do so without breaking your scheduled backup task.

If your target hard drive is an iPod, CCC will provide an additional option in the Settings tab: "Wait for iPod:iTunes sync to complete before copying data". When you bought your iPod, you probably did so with the intention of using it to enjoy your music collection. To this end, Carbon Copy Cloner recognizes that the primary purpose of an iPod is for music, and respects the synchronization period that occurs when you connect your iPod to your Mac. This option is enabled by default.

The Description tab indicates the name that you have provided for your backup task as well as a description of the task. CCC populates this description with the one provided in the main interface, but you may modify this description to suit your needs.

Managing and monitoring scheduled tasks

Scheduled task settings may be modified at any time. You can also temporarily disable a scheduled task by unchecking the box next to its name in the "Scheduled Tasks" list. To delete a task altogether, simply select the task in the "Scheduled Tasks" list and click the "-" button or press the delete key. If the task is running when you save modified settings or delete the task, the scheduled task itself will prompt for verification that you intend to end the running task. Choosing to not end the running task will not prevent the settings from being saved, but it will prevent the settings from taking effect. The new settings will take effect the next time you restart your computer or when you modify another setting and re-save them.

If you would like to run a scheduled task immediately, select the task in the "Scheduled Tasks" list and click on the Run button.

In addition to feedback provided in the interface, CCC records some information about your scheduled task in a log file. While the contents of this log file are generally intended for communication of problems to the developer, end users may find some of the information in this log helpful. CCC's log file is located at /Library/Logs/CCC.log. You can view the contents of this log by selecting "CCC Log" from CCC's Window menu.

Learn more about the CCC log file

Deferring and skipping scheduled tasks

Occasionally, a scheduled task will run at the most inconvenient time. Perhaps you are under deadline and don't have the patience for the hard drive performance hit of a system-wide backup. Or perhaps you are just about to pack up and hit the road. If you ever find the need to cancel a scheduled task at a particular time, CCC gives you two options for maintaining your backup regimen: 1) skip this particular scheduled run time or 2) defer this scheduled task to a specific time in the future.

When you skip a task, CCC will run the backup at the next scheduled interval. Deferring gives you more flexibility. Suppose that all you need are another twenty minutes to finish a project. Click defer and wind the clock forward twenty minutes -- CCC will run the task again then. Or suppose you realize that you forgot to bring your backup drive to work with you today and you have a scheduled task that runs every other hour. Rather than getting reminded of this four times, simply defer the backup to tomorrow.

Additionally, CCC offers you the option of permanently rescheduling a backup task. If, after a week or so, you realize that the originally scheduled time is really just too inconvenient, you can modify the start time in the defer panel by checking the box to "Reschedule all future events for this time of day". For more significant modifications to your backup scheduled, launch CCC and choose "Scheduled Tasks" from the Carbon Copy Cloner menu to edit your task.

What if ...?

What happens if no one is logged in when the scheduled task runs?
The scheduled task will run whether someone is logged in to the machine or not. If no one is logged in to the machine, CCC will run in the background without a user interface. CCC logs information to /Library/Logs/CCC.log, you can use that log file to monitor CCC progress (e.g. logged in remotely via SSH).

How is system sleep handled?
If a backup task is scheduled to run while your computer is sleeping, CCC will run that task immediately upon wake (CCC waits 10 seconds to allow your machine to establish network connectivity and spin up hard drives).

What if the backup drive is not available when the scheduled task runs?
If your backup hard drive is unavailable when the task is scheduled to occur (perhaps you're listening to tunes on your iPod at the time), CCC will report an error that the drive is not available and ask you to skip or defer the task. If you choose to skip the task, CCC will immediately run the backup when you reattach your hard drive. If you do not attach the hard drive to your computer before the next scheduled run time, CCC will prompt you again that the hard drive is missing.

How do scheduled tasks "work"

Carbon Copy Cloner Scheduled tasks are managed by launchd. Each scheduled task exists in the form of a property list file stored in /Library/LaunchDaemons. When these LaunchDaemons are loaded, an instance of "ccc_helper.app" is launched and configured with the scheduled task settings. While the Scheduler interface in CCC should be the primary means of configuring scheduled tasks, you can effectively deschedule a scheduled task by removing its configuration plist and rebooting your Macintosh.

			Getting more information about what is happening during the clone

Previous versions of Carbon Copy Cloner included a log that indicated the specific Unix commands that were running "Under the hood". CCC version 3 was completely rewritten and uses new techniques to back up your data. While some of those techniques still leverage the Unix underpinnings of Mac OS X, much of CCC now uses lower level features of the operating system that are not appropriate for logging (for example, you would not be able to "run the commands" in the Terminal application).

Learn more about (manually) creating a bootable backup of Mac OS X

Carbon Copy Cloner version 3 does, however, produce a log of output (/Library/Logs/CCC.log) that is useful primarily to the developer. You can use this log to verify the productivity of your scheduled tasks. To view CCC's log file, choose "CCC Log" from the Window menu. Beta versions of CCC will produce more output than non-beta versions. Additionally, you can manually enable debug logging by running this command in the Terminal:

defaults write com.bombich.ccc debug -bool YES

Debugging output is only useful to the developer, so don't enable debug logging unless instructed to do so for support purposes. CCC imposes a size limit of 1MB on the log file. When this limit is reached, the log is rolled over.

Comment on the "Data copied" figure reported in the CCC.log
This value indicates the data written that was actually consumed as disk space. For example, suppose you copy a single file that occupies a single 4Kb block (4,096 bytes) on the disk, but that file fills only 32 bytes of that block. This value represents the accumulation of those 32 byte values. This value will *not* correspond to the value of disk usage indicated in Disk Utility (not even close in most cases), Disk Utility reports the number of blocks occupied multiplied by the size of the block.

			Configuring Advanced Settings in Carbon Copy Cloner

[CCC Help] [Browse Help Topics]

Carbon Copy Cloner includes a few features that require a little consideration and research before using. These features are accessed by choosing "Advanced Settings..." from the Carbon Copy Cloner menu.

Clone to a subfolder on the target volume

There are two typical scenarios in which you may want to clone the contents of your source volume to a subfolder of the target volume rather than the root level of the target volume: 1) You maintain items at the root level of your target volume that you do not want to be erased, yet you want to do incremental backups, deleting items on the backup that were deleted from the source. 2) You want to use the target volume to back up more than one computer.

In the first scenario, your goal is to make regular, incremental backups to a target volume, deleting from the backup the files that you have deleted from the source. Except you don't want to delete items that were on the target volume before you started backing up! In general, these are conflicting goals. However, previous versions of CCC handled this situation quite gracefully. CCC version 3 uses a different approach to backing up than previous versions, and it is no longer capable of simply excluding preexisting items on the target volume. There are two solutions to this dilemma. The first is to use the "Clone to a subfolder..." setting. By specifying a subfolder (simply indicate the name of a folder, CCC will create it if it does not exist), CCC will copy the contents of your source volume into a single folder on the target volume. Any other files or folders on the target volume will be left unaffected. If you choose to use the "Delete items that don't exist on source", this rule will only apply to items within the subfolder that you have indicated.

While this seems like the perfect solution to the problem, note that you will not be able to boot from the backup volume, nor will you be able to select the subfolder as a source volume. You can still access your backup files via the Finder. An alternative to this method is to place items from the target volume that you don't want to lose into a directory prefixed with "_CCC", then specify the "Archive modified and deleted items" option. When using this option, CCC automatically ignores any directory prefixed with "_CCC", as that is the prefix used on the directories used to store archives of modified and deleted items. Another alternative is to clone to a disk image on the target. This option is explained below.

In the second scenario, your goal is to backup multiple computers. Despite that it is tempting, you are discouraged from using the "Clone to subfolder" feature to solve this problem. Instead, you should clone to separate disk images.

Learn more about backing up to and restoring from disk images

Run a shell script (before or after) the clone operation

If there is functionality that you need that does not exist within CCC, pre and post clone shell scripts may be the solution for you. For example, suppose you want to back up your Open Directory Master with CCC at regular intervals, but you know that a simply file-level copy will not properly back up an open database. The following pre-clone shell script will archive your OD master to a disk image for later restoration via Server Admin. It also dumps copies of Server Admin configurations as well as your MySQL databases:

#!/bin/sh

# Path to recovery directory (permissions should be 700 -- read-only root or admin)
recover="/etc/recover"

# mysqldump the databases
echo "Dumping MySQL databases"
mysqldump --user=root --password='s3kr!t' -A > $recover/mysql.dump

# grab the server configuration plists (only specify services that are enabled,
# use "serveradmin list" for a list of services)
echo "Generating serveradmin configuration plists"
services="afp dhcp dns ipfilter nat network swupdate vpn web"
for service in $services; do
    serveradmin -x settings $service > $recover/serverconfig/$service.plist
    sleep 1
done

# Backup Open Directory (if it's Thursday)
day=`date ''+%u''`
if [ $day != 4 ]; then exit 0; fi

od_backup=$recover/od_backup
ts=`date ''+%F''`
echo "dirserv:backupArchiveParams:archivePassword = s3kr!t" > $od_backup
echo "dirserv:backupArchiveParams:archivePath = $recover/od_$ts" >> $od_backup
echo "dirserv:command = backupArchive" >> $od_backup

serveradmin command < $od_backup

Pre-clone shell scripts run after you authenticate, and before any other tasks (e.g. mounting a target disk image, erasing the target). Post-clone shell scripts run after all other tasks have completed successfully. CCC passes as parameters both the source and target paths. For example, the following shell script:

#!/bin/sh

echo "Running $0"
echo `date`
echo "Source: $1"
echo "Target: $2"

Would produce the following output (typically in /Library/Logs/CCC.log, though you can redirect as desired):

Running /etc/postaction.sh
Wed Aug 14 21:55:28 CDT 2007
Source: /Volumes/Home
Target: /Volumes/Offsite Backup

Output from your pre- and post-clone shell scripts will be logged in /Library/Logs/CCC.log. CCC may drop the last output from your script, however, because output handling is handled asynchronously to avoid impacting performance of the backup task. To force all output to be logged, you can add "sleep 1" at the last line of your script.

Also, if your pre-clone script exits with a non-zero exit status, it will cause CCC to abort the backup operation. This can be used to your advantage if you want to apply preconditions to your backup operation. Alternatively, you can add "exit 0" at the end of your script to prevent any errors in your pre-clone script from aborting the backup task.

			Updating Carbon Copy Cloner

[CCC Help] [Browse Help Topics]

Carbon Copy Cloner version 3 includes a software update feature that periodically checks bombich.com for updates to CCC. To check for application updates, launch Carbon Copy Cloner and choose "Update CCC..." from the Carbon Copy Cloner menu. By default, CCC will automatically check for updates once a day. To change this preference, choose "week," "month," or "Never" from the popup menu indicating how frequently to check for updates. If you would like to check for updates manually, click the button labeled "Check for updates now". If a new version of CCC is available, a window will appear indicating new features, problems resolved, etc. If your version is current, you will receive a message indicating that you are up to date.

You also can choose to be informed of beta updates. Occasionally, beta updates are provided to field test updated version of CCC to confirm that code changes resolved a particular problem. In general, beta updates are only issued when a user has discovered a problem that the software developer cannot reproduce. Therefore, you should only apply beta updates when instructed to do so by Bombich Software.

Installing an update when you have scheduled tasks

When a software update is available and you choose to download and install it, you will be prompted to temporarily unload any scheduled tasks. Because scheduled tasks run as the system administrator user, you will be prompted to authenticate to unload these scheduled tasks. When the download and installation is complete, CCC will be relaunched and will prompt you to authenticate once again to reload your scheduled tasks.

Manually installing updated versions of Carbon Copy Cloner

If you decide to manually install a newer version of CCC, be sure to disable any scheduled tasks first. The Finder will not allow you to replace the original version of CCC unless scheduled tasks have been disabled.

			Frequently Asked Questions

[CCC Help] [Browse Help Topics]

• What happened to the "Repair permissions" option?
• Why don't the volume capacities as reported in Disk Utility match on the source and target?
• Can I use CCC to back up my BootCamp (Windows) partition?
• CCC requires an HFS+-formatted target volume. Why? And how do I format my new hard drive as HFS+?
• What are "Input/output" errors, and how should I deal with them?
• How frequent should my backups be?
• How do you check the accuracy of the backup?
• Can I do other things when the backup is being done?
• What makes a volume bootable?
• Can I backup directly to an AFP or SMB network file share? How about to a Time Capsule?
• How do I make the banners go away?
• How do you pronounce "Bombich"?

 

What happened to the "Repair permissions" option?

"Repair permissions" is not what I consider to be a task associated with backing up one's hard drive. It is at most a maintenance task, and more suitably a troubleshooting tool that should be used judiciously.

 

I just backed up my Boot Drive to a partition on an external hard drive. However, the volume capacities do not match. Should they? Should I be concerned there's more than a GB missing?

There are a couple legitimate explanations for a mismatch between the capacities reported in Disk Utility. First, when cloning using the "Incremental backup of selected items" cloning method, there is a list of items that are excluded from the backup either because they are ephemeral items regenerated every time your machine reboots, or they are not appropriate to back up or because they actually reduce the portability of your OS to another computer. An exhaustive list of those items is included in the CCC Help section labeled Configuring filters in CCC to limit what is backed up

While I don't recommend it, you could modify the list of items that CCC ignores by editing the "defaults.plist" file within the CCC application bundle. Note that these items are not ignored when using the "Backup everything" cloning method (that cloning method references a smaller, very conservative subset of items, also referenced in the defaults.plist file).

While the exclusion of these items explains much of the disk capacity discrepancy you may discover in Disk Utility, it does not explain it all. A user suggested the following scenario after performing a "Backup everything" clone to his target drive:

Boot drive - 39.67 GB used
Backup drive - 38.55 GB used

Should I be concerned there's more than a GB missing? Could this be a swap file or something? Is there an easy way to isolate what files are not on both?

A GB seems like a lot, but it's not surprising, not for 40GB used (the discrepancy increases with the amount of data on your boot volume).

I spent about 3 months head-down in the HFS+ filesystem specification trying to figure out why the contents of a cloned volume is always less than the boot volume (and it really is only that large of a difference when the source is the boot volume). I still can't explain it entirely, however I noticed that if I booted from the cloned volume, the difference was suddenly in the reverse.

The issue is that Disk Utility (and Finder Get Info for the volume) is misleading. The value that Disk Utility reports is indeed the amount of space consumed on your hard drive, however, it is not the amount of space consumed on the drive by all the files and folders that you can see. And I'm not referring to the other files as simply "invisible", these other files and directories that make up the rest of the space you're "missing" are simply not presented to the operating system. These items are filesystem implementation details, and it isn't possible to copy them directly with file-level copying tools.

Does this mean you're losing data? Absolutely not. It's pretty easy to prove it to yourself too, just boot from your cloned volume and take a look at the capacity reports in Disk Utility. Here's an example I performed on my test machine:

** Booted from the original source volume
Source: 5,258,776,576 bytes
Clone: 5,025,562,624 bytes

**Booted from the clone volume
Source: 4,996,599,808 bytes
Clone: 5,250,097,152 bytes

Weird, eh? Having stared at this issue for three months, having developed a utility that would carefully analyze every single file that I could find and copy, I am 100% confident that I'm not losing a scrap of information with my file-level copy engine for the "Backup everything" cloning method. What I have learned and I am confident in saying is that Disk Utility can't really be used as a good measure of success for your clone. That's not to say that what it reports is wrong, it is simply misleading.

 

Can I use CCC to back up my BootCamp (Windows) partition?

Backing up non-HFS+-formatted volumes is not currently supported. I am investigating how to provide this support in a future release.

 

CCC requires an HFS+-formatted target volume. Why? And how do I format my new hard drive as HFS+?

Mac OS X is installed on an HFS+ filesystem. The HFS+ filesystem defines many types of metadata that describe non-data attributes of your files. Creation date, access control lists, permissions and ownership, Finder flags, and extended attributes are among the various metadata types defined in the HFS+ standard. To adequately back up all of your files and their associated metadata, CCC requires that your backup volume is also formatted as HFS+.

Additionally, Macintoshes can only boot from hard drives partitioned with either the Apple Partition Map (APM) scheme (PowerPC- or Intel-based Macs) or the GUID Partition Table (GPT) scheme (Intel-based Macs). The hard drive icons that you see in the Finder are volumes. The partition scheme of a hard drive describes how volumes are physically defined on the hard disk. Every hard drive has exactly one partition scheme and at least one volume. When you "partition" a hard drive, you simply create multiple volumes on that hard drive.

See the section of CCC's documentation labeled "Formatting your hard drive for use with Carbon Copy Cloner" (in the "Tips for people getting started with CCC" section) for step-by-step instructions for partitioning and formatting a new hard drive for use with CCC.

 

What are "Input/output" errors, and how can I resolve them?

When copying to or from damaged media, or a disk with a damaged filesystem, CCC may report "Input/output" errors. If no other major errors are encountered, CCC will produce a dialog box indicating:

"CCC detected "Input/output" errors during the clone. These errors are indicative of filesystem damage or hardware trouble with the source or target volume. Examine the CCC.log to determine the nature of these errors and consider replacing the affected hard drive if filesystem repair is unsuccessful."

Correspondingly, the CCC.log file will list the files that CCC was attempting to read or write when the error occurred:

02:13:49 rsync: read errors mapping "/Applications/Keynote.app/Contents/Resources/Themes/Shared/flowers_h.jpg": Input/output error (5)
02:14:39 rsync: read errors mapping "/Applications/Keynote.app/Contents/Resources/Themes/Shared/flowers_h.jpg": Input/output error (5)
02:18:20 rsync: read errors mapping "Users/bombich/Movies/1984.mov": Input/output error (5)
02:18:24 rsync: read errors mapping "Users/bombich/Movies/1984.mov": Input/output error (5)
02:18:24 ERROR: Users/bombich/Movies/1984.mov failed verification -- update discarded.

The exact errors may vary, and some may be duplicated. If the affected file path begins with a "/" and CCC reports a read error, it is probably your source volume (e.g. the boot volume) that is affected. Errors affecting the target volume often indicate that "mkdir" failed or other write errors occurred, or the path will indicate the name of target volume.

Occasionally these errors are reported because your filesystem is damaged, but these errors typically indicate that your hard drive is dying. You have a narrow window of opportunity to back up the data from that disk to another hard drive. Time is precious; components could fail at any moment rendering the drive completely unmountable. Read activity is stressful on a dying volume, especially a full-volume backup. When I run into these errors on a hard drive that has not been backed up, I immediately back up the files that are most important. Once the most important data is backed up, I then try to do a full-volume backup. Once all important data is backed up, I then may try a filesystem repair utility (e.g. Disk Utility or Disk Warrior) if signs of imminent faliure are not present (e.g. particulary noisy drive, or loud, repetitive clicks).

What if the dying drive's volume won't mount?
More often than not, you're completely out of luck. I provided tech support at a University many years ago and had the opportunity to witness many failed drives. Occasionally we were able to revive a hard drive for small amounts of time by letting the drive cool down (somewhere cool and dry, not cold) and then powering it up attached to a service workstation (e.g. don't attempt to boot from it, you may not have enough time). When a drive doesn't mount, it typically goes to the recycle center or to DriveSavers if the data is worth the recovery cost. If you're reading this paragraph now because you're in this situation, my heart goes out to you.

 

How do you check the accuracy of the backup?

From a statistical perspective, booting from the cloned volume is an excellent way of sampling the efficacy of the clone. If the OS consumes 10% of the data on the volume for example, and booting requires that the clone be accurate (and it does), then you have a really good sample. If the cloned volume boots, you can reasonably conclude that the clone was executed accurately.

While you're booted from the cloned volume, launching applications, checking your email, firing up iPhoto, etc. will increase your "sample" size and give you more confidence that the clone was executed accurately.

 

Can I do other things when the backup is being done?

Yes and no, it really depends. Performance will be affected during the clone (especially the first one) as CCC reads the entire source volume and writes to the target volume. If your work is "disk bound" -- that is your applications are reading or writing to either the source or target, then you'll notice a performance hit. If you're just reading email or writing a Pages document, then you probably won't notice the performance hit.

Affecting the accuracy of the backup task is something else that should be considered. Typically it's OK to work from the source volume while you're copying it, with the understanding that if CCC copied a file, then you open it, make changes, save it, then CCC completes the backup task, the modified version of your document is not backed up (this time around). Typically that's no big deal, the modifications will get backed up the next time the backup task runs. More importantly, though, if you're working with large files (mounted disk image, Entourage email database, VMWare/Parallels container) during the backup operation, it is possible that those large files could be modified while CCC is backing up that file. This won't affect the source file, but there's a good chance that the backup version of that file will be corrupt. For this reason it is a good idea to stop using applications that may be modifying large files.

 

What makes a volume bootable?

Bootability comes down to a few simple rules:

1. The hard drive enclosure must support booting a Macintosh (applies to external hard drives only)
2. The computer must support booting from the hard drive's partition format (e.g. APM vs GPT vs MBR)
3. The cloned filesystem must have all the required components of Mac OS X
4. The cloned operating system must be properly "blessed"

When you buy a hard drive enclosure that you intend to use to boot your Mac, caveat emptor -- not all enclosures will boot a Mac (or any machine for that matter). Be sure to check that the manufacturer or vendor supports booting a Mac with the enclosure. You may even have to pay attention to whether they support booting your particular architecture (e.g. PowerPC vs. Intel). Some Western Digital enclosures had this problem. If you can't find solid proof that an enclosure will boot your Mac, don't buy it.

Once you have your new hard drive (in an enclosure or installed into your computer), you need to a) apply a partitioning scheme to the disk and b) format one or more volumes on the disk. Even if you do not plan to "partition" the disk, that is, slice the disk into smaller volumes, you still need to apply the correct partitioning scheme to the disk. Every disk has a partitioning scheme, even if it only has a single volume. I go into plenty of detail on this in this section of the documentation, so I won't rehash it here. Suffice it to say that PowerPC Macs and Intel Macs boot from different partition schemes, and each from a different partition scheme than what the overwhelming majority of hard drives ship with.

Rules #1 and #2 are external to the functionality of CCC. CCC will not apply a partition scheme to your disk, nor will it affect or modify your partition scheme in any way*. Also, if a hard drive enclosure won't boot Mac OS X, there's no software solution that will resolve that problem. Once you're sure you have those rules in hand, we can look at rule #3.

* OK, there's a small caveat to this for complete transparency. When doing a block-level clone, CCC will reformat the target volume. As a result, it must update the partition table entry for the target volume. Functionally, however, CCC is having no substantive effect on the partitioning of your disk.

Rule #3 is pretty intuitive -- if you want the operating system to boot, it must be whole. If you've cleared rule #2, CCC will tell you whether your target will have all the necessary components to boot Mac OS X. I should be clear that this is not exhaustive -- CCC will verify that the following items are present on the source and will be copied in their entirety to the target volume:

/Library
/System
/bin
/etc
/mach_kernel
/private
/sbin
/tmp
/usr
/var

So, if you choose to exclude /Applications or /Users for example, the cloned volume would still very likely boot. How much functionality you'd have is another story. Likewise, if the source volume's OS is not whole and, as a result, not bootable, CCC doesn't do an extensive analysis of the OS to confirm that it will boot. The bottom line, though, is that CCC will give a pretty good indication about whether your target volume will have the right OS components to actually boot.

Rule #4 is perhaps the least understood, so I'll do my best to explain it here. When a Macintosh boots, this happens:

1. The computer performs a Power On Self Test. When that test succeeds, you hear the characteristic Macintosh startup chime.
2. The computer's pre-boot firmware (software that is embedded in a chip on the computer's motherboard) takes account of the hardware that is present, builds a device tree, and determines which hardware device to boot from (more on this in a bit). For the sake of simplicity, let's suppose a machine is configured to boot from particular volume on a particular hard drive.
3. The firmware of the computer accesses the filesystem of that volume and determines the location of the file, or folder containing the file, that is "blessed" to initiate the operating system.
4. That file is executed by the firmware and control of the hardware is handed over from firmware to the booter.
5. The booter executes the kernel of the operating system and pre-loads a kernel extensions cache.
6. The kernel initiates the rest of the boot process (primarily by executing launchd)

The gist of all of this is that every bootable volume must indicate the location of the system folder. The path of the folder turns out to be irrelevant, because the HFS+ filesystem simply stores the "inode" of this particular folder. The inode is basically like a street address for the file, it indicates where on the disc platter the folder is located. This information is stored in the HFS+ Volume Header, but you can easily see the current state of this information using the "bless" command in the Terminal application. For example:

bash-3.2# bless --info /
finderinfo[0]: 116 => Blessed System Folder is /System/Library/CoreServices
finderinfo[1]: 546345 => Blessed System File is /System/Library/CoreServices/boot.efi
finderinfo[2]: 0 => Open-folder linked list empty
finderinfo[3]: 0 => No OS 9 + X blessed 9 folder
finderinfo[4]: 0 => Unused field unset
finderinfo[5]: 116 => OS X blessed folder is /System/Library/CoreServices

The relevant information in this case is that the blessed system folder is at inode 116, and that path (for the human reader) is /System/Library/CoreServices. PowerPC-based Macs need only this piece of information to boot. PPC Open Firmware will find that directory, then execute the file named "BootX" within that directory. Intel-based Macs also use the "Blessed System File" information. In this case, that is the file at inode 546345 and (again, for the human reader), that file is located at /System/Library/CoreServices/boot.efi.

It is important to note that blessing a volume is different than specifying a boot device. Blessing a volume simply updates the information in the HFS Volume Header that indicates where the blessed system folder and file are located. When you specify a particular volume as the startup disk, on the other hand, the computer stores a reference to that volume in the "Non volatile RAM" -- basically a small section of RAM whose contents are not lost when the machine loses power or is shutdown. The importance of this disctinction, and all four of these rules for that matter, is that simply setting a volume as the startup disk may not be sufficient to actually boot from that volume.

 

Can I backup directly to an AFP or SMB network file share? How about to a Time Capsule?

CCC can back up directly to an HFS+ formatted local volume, or to a disk image on any writable network volume. CCC cannot, however, backup directly to a network filesystem (e.g. AFP, SMB, Airport Extreme "Airdisk", or Time Capsule). There are significant technical limitations to backing up an HFS+ filesystem to a non-HFS+ filesystem (most notably preservation of ownership and permission information), therefore I recommend and support backing up only to a disk image on non-HFS+ filesystems.

 

How do I make the banners go away?

Please see the section of CCC's documentation labeled "What does CCC cost?" for complete details on this subject.

 

How do you pronounce "Bombich"?

Like the pen, not the dog. (Bombick) ;-)

			Carbon Copy Cloner Public Source Code Credits

[CCC Help] [Browse Help Topics]

Localizations

I would like to thank the following people for their generous help in translating CCC into other languages:

• German: Martin Kowalewski
• Japanese: Tadahisa SUGISAKI
• Italian: Francesco Magariello
• Spanish: Victor Bottacco [www.cool-crew.com]
• Dutch: Alexander Henket
• French: Antoine LATOUR [www.sosmac-fr.com]

Opensource Credits

Carbon Copy Cloner contains portions of source code available under the Apple Public Source License. That code may be downloaded by clicking the links below.

• vsdbutil_main.c (View my modifications: vsdbutil.h and vsdbutil.c)

View the APSL 2.0 license

Carbon Copy Cloner also includes, independently in binary form, rsync version 3.0.6. rsync is made available under the GNU General Public License. Per the license requirements, the source code and my modifications may be downloaded via the links provided below. This modified software is provided at no cost and with no warranty, also per the GNU GPL.

• Download the complete rsync 3.0.6 project
• Download the rsync 3.0.6 patches
• Download the diff file (diff between 3.0.6 + [crtimes.diff, fileflags.diff, and backup-dir-dels.diff] and my modifications)
• View the GNU GPL

Carbon Copy Cloner is not a derivative work of rsync, nor does it depend on rsync for ordinary operation. Rsync is included as a convenience and an option, and called in binary form as required.

			CCC Release History

[CCC Help] [Browse Help Topics]

Originally published on January 18, 2002, Carbon Copy Cloner was the very first native cloning utility for Mac OS X. For version 3, Carbon Copy Cloner was completely rebuilt with a new suite of features to meet the growing needs of Mac OS X users. In addition to the fast disk-to-disk cloning, CCC is now a full-featured backup utility as well.

Among the new features in CCC 3 are:

• Support for block-level disk-to-disk clones.
• Synchronization built-in, not bolted on.
• Support for backing up across the network to another Macintosh.
• Advanced scheduling capabilities -- choose what days to run your backups and how frequently they should run. You can also defer a backup if it starts at an inopportune time.
• Now you can create a scheduled task that backs up your data whenever you attach a specific hard drive or iPod.
• The ability to drill down into folders to select exactly what gets copied and what doesn't (you can drill down indefinitely).
• A more responsive interface and the ability to stop the clone.
• More accurate feedback during the clone.
• The ability to pick up where a previously aborted backup task left off.
• More information about your volumes are available within the CCC interface.

v. 3.3 (27), September 21, 2009

• Added support for HFS+ filesystem compression that was introduced in Snow Leopard.
• To correspond with how the Finder and Disk Utility report these values on Snow Leopard, CCC will now use base 10 for reporting MB and GB on Snow Leopard. CCC will continue to use base 2 to report these values when booted from Leopard or Tiger.
• Improved the performance of backing up a large number of files with extended attributes.
• It is no longer a requirement that CCC be installed on media that supports the setuid bit.
• Added a bootability notification that will notify users when a target volume's underlying disk is partitioned with the MBR partitioning scheme (rather than the Apple-recommended GUID or APM partition scheme).
• Increased the increment value of the disk image segment size stepper from 1 to 25. Now it takes mere seconds to get from 650MB to 4.6GB.
• Addressed an issue in which the source and target menus would not be properly updated if a disk disappears unexpectedly in the middle of a backup task.
• CCC now properly excludes the Time Machine database when backing up a hard drive using the "Backup everything" cloning method in file-level mode.
• Much like the Snow Leopard update, this release includes hundreds of tweaks and adjustments to improve performance and reliability.

v. 3.2.1 (24), March 30, 2009

• Resolved interface issues with non-English localizations.
• Resolved an issue in which, in some circumstances, rsync was unable to create a directory if the parent directory was locked.
• Addressed a codesigning issue that would prevent CCC from launching in some cases on Mac OS X Tiger.
• Resolved an issue in which the Authentication Credentials installer package would not install on certain installations of Mac OS X Tiger.

v. 3.2 (22), March 18, 2009

• Prior to version 3, CCC would not delete items at the root level of the target volume if those items were not present on the source volume. This was a convenient feature, but due to some fairly significant underlying changes in CCC 3, that feature was not brought forward. This feature is now available again in version 3.2 and later via the "Protect root-level items on the target" option. See the documentation for more details on the implementation of this feature.
• Implemented filters support for remote source volumes.
• CCC no longer disables non-HFS formatted volumes in the source and target lists. Rather, selecting these non-supported filesystems as a source or target will produce a helpful dialog box indicating how to proceed with those volumes.
• The description of what will happen during a "Backup everything" task has been updated to more accurately reflect what actually occurs.
• CCC now correctly reports on the bootability of mirrored volumes on PowerPC systems.
• Resolved a few minor issues with cropped text in non-English localizations.
• CCC will now report IO errors via a dialog box every time they are encountered. Previously, non-IO related errors encountered after IO errors would take precedence, and IO errors would only be reported in the CCC log.
• Addressed an issue in which CCC would fail with a generic error when running out of space for temporary files on the target volume.
• Included an updated version of rsync 3.0.5.
• Resolved an issue in which locked folders caused synchronization errors in rare circumstances.
• Resolved several rsync-related issues related to getting, listing, setting, and removing extended attributes.
• Resolved an issue in which CCC would prompt the user to run a scheduled task (with a remote Macintosh as the target) when the network connection was re-established even if the task had been explicitly deferred.
• CCC now creates its own key pair for ssh communication with other Macs on your network, rather than using any pre-existing key pairs.
• CCC now mounts disk images at custom mount points in /tmp rather than in the default location of /Volumes.
• Resolved an issue in which disk images could not be created on AFP or SMB network shares.
• Resolved an issue in which the failure of certain built-in tasks would indicate that there was an error with a preflight script.
• Several updates to the documentation: Expanded on the Tips section, added extensive coverage of the new "Protect root-level items on the target" feature, updated instructions on restoring from a disk image, minor updates to the "Backing up to a remote Macintosh" section (plus a large addition on backing up multiple Macs to a single "server"), and added several items to the FAQ section.

v. 3.1.3 (21), December 8, 2008

• Fixed an issue in which the target volume would not be bootable in some cases.
• Fixed an issue in which a block-level clone would be attempted inappropriately.
• Included updated localizations including a complete French localization.
• CCC should no longer check for updates if a backup task is running.
• CCC now ignores Time Machine backup databases. Time Machine backups will not be backed up (CCC does not support backing up Time Machine backups).
• Messages indicating that a scheduled task's target disk has reappeared are now automatically dismissed after 60 seconds allowing the task to run.
• Fixed an issue that would prevent the saving of scheduled tasks upon the very first launch of CCC.
• CCC no longers permits non-HFS+ volumes as a selectable source volume (in support of the defined system requirements).
• Fixed an issue in which files or folders with special characters (e.g. "[", "]", and "*") could not be excluded in an "Incremental backup of selected items" backup task.
• Fixed an issue in which CCC would report a generic error rather then indicating that a backup task failed because there was not enough free space on the target to accommodate large files that had been modified since a previous backup.

v. 3.1.2 (20), October 13, 2008

• Resolved an issue with the syncronization engine that caused Incremental backups to fail in some cases.
• The "Backup everything" cloning method now properly handles inherited ACLs.
• The "Backup everything" cloning method is now 25% faster during a file-level copy. It consumes far lass time when backing up to an existing backup.
• Fixed a bug in which creation dates of modified files were not properly preserved on PowerPC-based Macs when using the Incremental backup method.
• I now provide more insight into how to resolve an error message caused by trying to replace an item on the backup volume that is of a different type than the item on the source volume.
• Pre and post-clone script output is now directed to the CCC.log file. CCC also aborts more gracefully when pre-clone scripts exit with a non-zero exit status.
• The Stop button in the cloning progress panel no longer has focus. Users that press the space bar to wake a dimmed display will be pleased that this action no longer aborts a backup operation.
• Fixed an issue in which CCC relied solely on the HFS+ volume UUID (Universally Unique Identifier) for identification, which, in rare cases, led to CCC trying to clone a volume to itself.
• Reformatted the Help content for easier printing. The entire set of documentation can be printed from any page in the documentation. Documentation also now opens in your favorite web browser.

v. 3.1.1 (13), July 7, 2008

• Included version 3.0.3 of rsync (minor bug fixes).
• Fixed a bug in which clicking "Proceed" when plugging in a target volume does not cause the scheduled task to proceed if that task is scheduled to back up only when the target drive is reattached.
• Fixed a bug in which extended attributes on a file would not be preserved if that file was locked on the source volume (only affected the "Backup everything" backup method).
• Fixed an issue in which CCC would not report success if minor errors were encountered. Upon encountering minor errors, CCC now reports that the backup task completed, but encountered errors. This also permits any post-backup tasks to occur, such as blessing the target volume and running post-backup scripts.
• Fixed an issue in which deferred tasks would run late if the machine slept.
• Fixed an issue in which the CCC application would not launch if it was initially installed by another user on the system.
• For the "Backup everything" cloning method, CCC no longer defaults to erasing the target device. CCC will warn if an existing OS installation on the target may conflict with the installation that is being backed up.
• Implemented support for block-level cloning to a disk image (when the source volume can be unmounted) and improved the performance of file-level backups to a disk image. These changes represent a 2-5x performance improvement.
• Disk image segmenting now works as advertised.
• Resolved an issue in which choosing to encrypt a disk image would cause CCC to hang on Leopard.

v. 3.1 (12), March 24, 2008

• Implemented rsync 3.0.0 to provide even greater fidelity when backing up using the incremental backup method
• Improved the wording of options in the interface to make it more clear what CCC is doing
• Implemented "bootability" checks -- CCC now reports whether the backup volume will be bootable based upon the options you have chosen
• CCC now offers a dialog box to opt out of a backup task that is scheduled to occur when the target volume is reattached
• Resolved an issue in which an existing disk image selected as the target would not get mounted during a "Copy everything" backup
• When creating a new sparse image during a "Copy everything" backup, the capacity of the disk image is now the same as the capacity of the source volume rather then just enough space to accommodate the files that will be copied
• Resolved issues with installing the Authentication Credentials installer package from multiple source machines on a single target machine
• Adjusted permissions of the archival folders so that admin users can modify their contents
• Adjusted permissions of target disk image so that admin users can mount it read-write
• Resolved an issue in which scheduled tasks would not run upon reboot (Leopard only)
• Resolved an issue in which a backup using the "Copy everything from source to target" method would fail soon after erasing the target volume
• CCC no longer allows the scheduling of tasks that erase the target volume
• Fixed a regression in which the "invisible" flag is not preserved when performing a backup with the "Copy everything" method (Leopard only)
• CCC no longer errantly warns the user that specifying "/" as the path on a remote source volume will overwrite the boot volume
• Resolved an issue in which specifying a path with a space in it would cause CCC to back up to the wrong location on a remote Macintosh, potentially resulting in data loss

v. 3.0.1 (11), October 23, 2007

• Fixed an issue that caused creating new disk images to fail
• Fixed an issue that would cause backup to a remote Macintosh to fail
• Fixed an issue that caused "Failed to chown" messages to appear in the log and caused CCC to report that the synchronization engine had failed
• Modification times of folders and applications are now properly preserved when using the "Copy everything" cloning method
• Fixed an issue in which locked files were not properly deleted (as necessary)
• Fixed an issue in which CCC reported that it could not enable ownership on the target volume
• CCC now explicitly disallows non-HFS volumes (this clears up confusion on what target volumes are supported)
• Fixed an issue in which CCC errantly reported that it could not archive some items during a "Copy selected items" clone
• Resolved several localization issues and included localizations for French, Russian, Korean, Swedish, and Dutch
• The Authentication Credentials Installer package no longer installs CCC's version of rsync into a location commonly in $PATH
• Minor tweak to improve performance when copying to a sparse disk image created by CCC on a network volume
• Fixed an issue that would cause some target volumes to not be bootable
• Fixed a cosmetic issue in which the amount of data copied in the CCC.log file was grossly incorrect

v. 3.0 (10), September 18, 2007 (Official non-beta release)

The change list is over 100 lines long, the items listed below are an executive summary

• Several performance and fidelity enhancements to the rsync engine
• Created a new copy engine for file-level, full-volume clones
• Resolved issues of certain normally-invisible files appearing on non-booted target volumes
• Numerous interface enhancements
• Completely redesigned the Scheduler interface
• I now provide additional statistics during the clone (time elapsed and data copied)

v. 3.0-b5 (8), March 5, 2007

• Resolved an issue with the "Check for updates now" button returning an error suggesting that you are not connected to the Internet.
• Resolved an issue where a message indicating that CCC had trouble enabling permissions on the target volume appeared even if permissions were already enabled on the target volume.
• Resolved an issue in which a backup done with the "Copy selected files" option would incorrectly modify the creation date or modification date of certain files.
• Resolved an issue where resource forks and other extended attributes would indiscriminately be copied every time a "Copy selected files" task was run, even if those items already existed on the target and had not changed.
• Fixed a cosmetic issue related to resizing the Scheduled Tasks window.
• The background tools included with CCC are now built Universal.
• Resolved an issue where repeating a disk-to-disk clone would fail indicating that you must choose a source and despite that a source and target are already selected.
• Imposed a debug log file size limit.
• The clone description is no longer updated during the clone (caused unnecessary panic among some people).
• CCC now properly prevents the unmounting of a source or target disk during a clone.
• Resolved a minor cosmetic issue related to deselecting items in the items to be copied table.
• Support for "incremental" backups -- modified and deleted files are saved to a time-stamped directory on the target.
• CCC prevents a source or target volume from being unmounted during a clone.
• Support for checksumming a "Copy selected files" operation for users running 10.4.9.
• A custom build of rsync is now included with CCC that resolves several bugs listed above.
• Included preliminary localizations for French, Japanese, Spanish, and Swedish.

v. 3.0-b4, February 16, 2007 (First public beta)

• Support for block-level disk-to-disk clones.
• Support for backing up across the network.
• The ability to drill down into folders to select exactly what gets copied and what doesn't (you can drill down indefinitely).
• A more responsive interface and the ability to stop the clone.
• More accurate feedback during the clone.
• The ability to pick up where a previously aborted backup task left off.
• More information about your disks are available within the CCC interface.
• Advanced scheduling capabilities -- choose what days to run your backups and how frequently they should run. You can also defer a backup if it starts at an inopportune time.
• Now you can create a scheduled task that backs up your data whenever you attach a specific hard drive or iPod.