clone mac hard drive disk utility catalina

The latter have to start their boot process from their internal SSD, even when starting up from an external disk.

With Big Sur, cloning all but ground to a halt: first, the only method to perform that, asr, suffered a serious bug and didn’t work, then it became clear that the complexities of the boot volume group made cloning inherently less reliable.Īt the same time, Recovery Mode improved considerably, as it had to for Apple silicon Macs.

Apple provided Remote Recovery, but that was so ponderously slow that it couldn’t replace the second bootable disk.įrom High Sierra through to Mojave, changes brought by the introduction of APFS made the second boot disk just as attractive, but Catalina went all complicated, with its more elaborate volume layout. That had the added bonus that you could then use the intermediate disk in an emergency, when your regular boot disk suffered problems.įrom Lion to Sierra, Recovery Mode was a bonus, but because Recovery depended on a hidden HFS+ volume on the same disk, it was vulnerable to many of the same problems as the system volume on that disk. Because those were rotating hard disks and vulnerable to fragmentation, one simple way to defragment all your files and free space was to clone a volume from one disk to another, and back again. Those with Macs with multiple internal disk bays, like the Mac Pro and its predecessors, frequently cloned volumes and whole disks. Long before Apple came up with Recovery Mode in Mac OS X Lion 10.7 in July 2011, there were only two practical options for tackling serious problems: single-user mode (SUM), or another bootable disk. The first version of Mike Bombich’s Carbon Copy Cloner in January 2002, for Mac OS X 10.1 Puma, changed that. Prior to that, it was usually easy enough to copy the System and other supporting files when necessary. If you can’t reliably clone your current system, what options are there?Ĭloning Mac systems didn’t really start in earnest until the release of Mac OS X. One question that has arisen is how best to make an external bootable disk in preparation.

Now we’re into October, all eyes are on Ventura, promised for release in the next four weeks, assuming Apple doesn’t make it a special Hallowe’en edition.

Clone mac hard drive disk utility catalina