Time Machine Drive Questions

(Jack Clay) #1


My system: iMac (Retina 4K, 21.5-inch, Late 2015), 16GB, 1 TB Fusion Drive, High Sierra (moving to Mojave soon)

My backup system:

  • 2TB Time Capsule using Time Machine
  • 1TB IOmega USB external drive using Time Machine and SuperDuper
  • 500GB OneTouch USB external drive using SuperDuper

The Iomega backup drive is full and I’ve ordered a WD 4TB drive recommended by the Wirecutter. The imminent arrival of the drive brings to mind several issues that I’m sure members of this list can help me address.

  1. Is is possible to move the time machine backup file (Backups.backupdb) from the Iomega drive to the new drive so I can preserve the backup history on the new drive? If so, what’s the best way to do it?

  2. I plan to format the WD drive before using it. Because I will be moving to Mojave, and I understand my Fusion Drive will be converted to the new file format (HPFS?), should I format the WD drive using the new file format? If so how can I do that before I install Mojave?

  3. I think I’d rather have SuperDuper backups on separate drives (at least virtually) from the Time Machine files. Is there any reason not to partition the new WD drive into two ‘drives’ to keep things separate? (I realize a physical drive failure would doom both, but I do have the IOmega and OneTouch drives to use for SuperDuper, and the Time Capsule will still have the Time Machine files.)

Thanks for any thoughts!

(Simon) #2

I think the external HDD can remain HFS+. That way you’re not forced to go to Mojave. Once you have Mojave and you’re comfortable you can always switch to APFS to get its benefits over HFS+ on the HDD.

I would also prefer my clones on a different volume than my TM backups. In fact, I usually tend to keep them on different disks, but having them on the same disk (with two different partitions) has the added benefit that it makes the “TM disk” bootable, which it otherwise by itself would not be. If you chose a little over 1 TB for the clone partition on your new HDD, that will easily be enough for a full clone of your 1 TB fusion drive while leaving ample space for your TM backups. If you plan to never use all of that 1 TB fusion driver you can chose to partition a bit tighter.

I recall moving one TM backup from an old small HDD to a new big drive. I remember cloning it to the new disk with DiskUtility and then simly making sure TM was set up to use the new disk. Worked just fine. I kept the old small disk around to be sure, but I’ve never had to go back to it since. If you’d prefer to do it through manual copy rather than cloning, Apple has extensive instructions here:

(Alan Forkosh) #3

Note that a Time Machine Disk must cannot be formatted as APFS. See https://support.apple.com/guide/mac-help/types-of-disks-you-can-use-with-time-machine-mh15139/mac

For my laptop, my primary backup disk is a 2TB Seagate portable drive partitioned into a 1TB Carbon Copy Cloner clone and a 1TB Time Machine (the laptop has a 1TB SSD). Note4 that the clone is somewhat incomplete as I don’t clone the photo and music libraries (since they are extracts from the versions on my desktop). Every week or so, I plug the drive into my laptop and perform the CCC Clone. The Time Machine, of course, kicks in automatically. When both are done, I eject the partitions and disconnect the disk.

I should note that when I travel, I carry a 4TB HDD partitioned into a 3TB drive with a clone of my 3TB desktop (copied from the latest nightly clone) and a copy of the latest laptop clone. This is useful in 2 ways:

  1. If I need a copy of a file from my desktop while traveling, I can copy it from HDD.

  2. Should my home become inaccessible, I could recover my computer status by purchasing and working with new hardware (pusing that further down the list of concerns in that circumstance).