What makes a volume bootable?

Product: 
ccc4

Bootability comes down to a few simple rules:

Backing up to/from network volumes and other non-HFS volumes

Product: 
ccc4

In addition to backing up to volumes formatted with the macOS standard "HFS+" format, CCC can back up user data to network volumes (e.g. AFP and SMB via macOS and Windows File Sharing) and to other non-HFS+ formatted volumes such as FAT32. Non-HFS+ formatted volumes are presented in CCC's Source and Destination selectors in the same manner as HFS+ formatted volumes, so there are no special steps required for backing up to or from these filesystems.

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

Product: 
ccc4

For improved detachability, macOS 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 drive enclosure is attached, you can detach those hard drive enclosures 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 CCC backup task that runs when no user is logged in, the destination volume may be unavailable.

Backing up large files, mounted disk images, and Virtual Machine containers

Product: 
ccc4

Mounted disk images and running Virtual Machine container files pose an interesting problem to incremental backup utilities. By simply being mounted and accessed (e.g. via browsing the contents, booting the VM), the content of these large files are subject to modification by the applications that use those files.

Using the ccc Command Line Tool to Start, Stop, and Monitor CCC Backup Tasks

Product: 
ccc4

Carbon Copy Cloner includes a command line utility that allows you to start, stop, and monitor the progress of specific CCC backup tasks. The utility is located inside of the CCC application bundle. To get basic usage instructions, invoke the utility without arguments in the Terminal application, e.g.:

Performance Suggestions

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ccc4

There are several factors that affect the performance of your backup tasks. Here we describe the most common conditions that affect backup performance, and offer some suggestions for mitigating the effects of those conditions.

Restoring from a backup on a remote Macintosh

Product: 
ccc4

Restoring files from a remote Macintosh is nearly the same procedure as backing up to a remote Macintosh:

I want to defragment my hard drive

Product: 
ccc4

A welcome side-effect of cloning one volume to another is that the files on the resulting volume are largely defragmented. While fragmentation is not as significant of an issue as it used to be (e.g. in the Mac OS 9 days), people that have begun to fill the last 10-15% of their boot volume may see some performance benefit from defragmentation. If you find yourself in this situation, this is also a really good time to consider migrating to a larger hard drive altogether, or to an SSD, which is not affected by fragmentation.