How do i format a mac external hard drive for time machine

Hi,

I bought a new 2T Passport external Hard Drive for my 2015 MBP - running macOS Monterey (ver 12.3.1) The connection between the external hard drive is through USB. I normally encrypt my drives. I forget if Time Machine does the encryption or if that's only done through Disk Utility. That's a minor question on my part. But, the bigger question is

for my external hard drive?

1. APFS (Encrypted)
2. APFS (Case-sensitive, Encrypted)
3. Mac OS Extended (Journaled)
4. Mac OS Extended (Case-sensitive, Journaled)

I've had my MBP since 2015 - I was able to encrypt Time Machine backups when there was only Mac OS Extended to choose from (so.... that makes me think Time Machine does the encryption.

Any help, advice, or comments very much appreciated!

Any of those will work fine on a hard drive. I used APFS on a hard drive in the past and never had any issue. But APFS is optimized specifically for SSD, even if it works on hard drive. So I would recommend you MacOS Extended.

Any of those will work fine on a hard drive. I used APFS on a hard drive in the past and never had any issue. But APFS is optimized specifically for SSD, even if it works on hard drive. So I would recommend you MacOS Extended.

Thanks! Does it matter if I choose case sensitive or not? The external hard drive would only be used with Time Machine. Also, there's no option to select encrypt when using MacOS Extended (Journaled). How is encryption accomplished normally (when using the hard drive as an external to store, say, your music or video files)?

Thanks! Does it matter if I choose case sensitive or not? The external hard drive would only be used with Time Machine. Also, there's no option to select encrypt when using MacOS Extended (Journaled). How is encryption accomplished normally (when using the hard drive as an external to store, say, your music or video files)?

It's up to you, personally I would not use it, because the Mac itself is not case-sensitive by default. If, for example, you have a file named file.pdf in a specific folder, case-sensitive encryption would allow you to save File.pdf or fiLe.pdf in the same directory, while non-case sensitive would see them as the same file and ask you to change the name. But using it only as a Time Machine back-up drive, I don't think it would make a difference.

I'd say that if you're not sure you need case sensitive, you probably don't and it's probably best to use non-case sensitive, because some apps and softwares don't recognize case-sensitive files and it can create confusion

APFS is optimized to work much better with Time Machine, so that should be your choice.

Also, you will find that under Monterey, Time Machine will convert the format to case sensitive even if you just format to plain APFS.

Assuming you want your backup encrypted (no reason not to), you should just go ahead with APFS encrypted case sensitive.

APFS is optimized to work much better with Time Machine, so that should be your choice.

Also, you will find that under Monterey, Time Machine will convert the format to case sensitive even if you just format to plain APFS.

Assuming you want your backup encrypted (no reason not to), you should just go ahead with APFS encrypted case sensitive.

Exactly, Time Machine reformats regardless so doesn’t matter

I think CarbonCopyCloner recently told me to NOT use case sensitive.

The other question not asked, is why is anyone (including myself) still using TimeMachine?
I lost count of the number of times it has failed me - especially when coupled with an Apple TimeCapsule.
I still do it to hardwired HDs and SSDs because I'm afraid one day CCC will fail too (so I try to have both going), but so far, CCC has been much more reliable. Maybe the best $25 I ever spent on software.

GOOD LUCK!

It's only a matter of time before macOS is every bit as awful as Windows. I'm surprised we got this far after Steve Jobs died.

I think CarbonCopyCloner recently told me to NOT use case sensitive.

The other question not asked, is why is anyone (including myself) still using TimeMachine?
I lost count of the number of times it has failed me - especially when coupled with an Apple TimeCapsule.
I still do it to hardwired HDs and SSDs because I'm afraid one day CCC will fail too (so I try to have both going), but so far, CCC has been much more reliable. Maybe the best $25 I ever spent on software.

GOOD LUCK!

I would have understood your position prior to Monterey. Apple's ongoing, and yet to be finished, move to APFS has, in Monterey, delivered a solid and quicker TimeMachine. I've gone back to it. Pleased to the point the staggered clones I've been doing for over 20 years are now down to one before an OS update and another right after. If you haven’t tried it recently, may want to give it another chance.

I would have understood your position prior to Monterey. Apple's ongoing, and yet to be finished, move to APFS has, in Monterey, delivered a solid and quicker TimeMachine. I've gone back to it. Pleased to the point the staggered clones I've been doing for over 20 years are now down to one before an OS update and another right after. If you haven’t tried it recently, may want to give it another chance.

Same here. I find it works quite well since the switch to APFS. I have an SSD Velcroed to the back of my monitor and run TM full time.

I use CCC with a separate drive once a week or so.

Does the Passport have a platter-based drive inside?
If so, format it to HFS+ (Mac OS extended with journaling enabled, GUID partition format).

Does it have an SSD inside?
If so, format it to APFS, GUID partition format.

Aside:
I've never used time machine, so don't know if the version that comes with Monterey needs APFS to work.
But HFS+ is "the better choice" for platter-based drive (again, IF it's compatible with tm)

APFS is the newest format, the Journaled is old and I think that it dated back to 1998?

Does the Passport have a platter-based drive inside?
If so, format it to HFS+ (Mac OS extended with journaling enabled, GUID partition format).

Does it have an SSD inside?
If so, format it to APFS, GUID partition format.

Aside:
I've never used time machine, so don't know if the version that comes with Monterey needs APFS to work.
But HFS+ is "the better choice" for platter-based drive (again, IF it's compatible with tm)

The Passport is a mechanical drive. BTW - what does HFS+ mean?

HFS+ is the old/classic filesystem.

Ditto what @Sheepish-Lord and @Weaselboy said: Time Machine setup will reformat the drive to APFS at initial setup, so no need to worry about what to format the drive as. Specifically, there is a Role in APFS for Time Machine volumes, so drive will be reformatted APFS and a volume with Time Machine Role gets created in the new container.

I was trying to format a TM HDD to HFS+ on a machine running Monterey it always got re-converted back to APFS by Monterey. The only way I could keep it as HFS+ was to wipe the drive on an 2011 iMac running High Sierra and set it as a TM drive on that machine. Then move the drive to the machine running Monterey.

One thing I noticed is that if you create a TM drive (APFS) on my iMac or MacBook Air and you run First Aid it always generates an error. I have several APFS formatted TM drives that this happens with. Same result on 3 different machines. When you convert one to TM (HFS+) and run First Aid no errors.

File system check exit code is 65. File system verify or repair failed (-69845) Happens consistently but only on HDD drives that that are formatted as APFS for TM use.

Yeah... that is a Disk Utility bug. You can check an APFS TM drive with this Terminal command.

Code:

diskutil verifyvolume /dev/disk7

If there are errors, you can run this command.

Code:

diskutil repairvolume /dev/disk7

You may need to change the disk7 part depending on your setup.

You can find the correct number by running diskutil list.

You really are better off running TM with APFS though.

If encryption is on, the following needs to be done as well:

sudo diskutil apfs unlockVolume /dev/diskXXX -nomount

Instead of of diskutil verifyvolume, can also call fsck_apfs:

sudo fsck_apfs -n /dev/diskXXX

Or, from Recovery, Disk Utility will work there.