I’m at present utilizing a single disk (disk 1) for my Time Machine backups. I wish to migrate this to a two-disk RAID1 quantity. I have already got a second disk (disk 2) that’s equivalent to my Time Machine disk. I would like the ultimate RAID1 to be composed of disk 1 + disk 2 (each as RAID slices).
The issue is that Disk Utility (macOS Catalina 10.15) won’t let me create a brand new RAID1 quantity except a minimal of two drives are used for the preliminary setup. Preliminary RAID quantity setup requires wiping all drives. One of many drives I wish to use for the RAID (disk 1) accommodates my present Time Machine backups.
I hoped that I might be capable of initialize the RAID1 with solely disk 2, migrate the Time Machine backups from disk 1 to the disk 2 RAID, then wipe disk 1 and add it to the RAID1 quantity. I’ve not been capable of finding any method to do that. Is it doable?
Because it stands, the one different choice I appear to have is to dump the present Time Machine backups onto a 3rd drive, create the RAID1 with disk 1 + disk 2, then transfer the information again to the brand new RAID quantity. However that is non-trivial, as a result of the Time Machine backups include a number of TB of information and a number of other million complete recordsdata. Since we’re speaking about normal 3.5″ arduous drives right here it additionally limits the information switch to ~200MB/s in one of the best case; merely enumerating all of the recordsdata within the Time Machine backup takes 12 hours++ earlier than knowledge switch even begins.
Is there any option to accomplish this activity of making a brand new RAID1 quantity utilizing solely a single free HDD after which migrating each the information and second HDD into the RAID quantity in fewer transactions? Are there every other methods that may make this course of simpler?
