Shared Linux and Mac OS external drive for Time Machine

[rib00]

I have an HDD that I use with my Linux computer. There is unallocated space.

I would like to create a partition on the HDD for use with Time Machine.

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tldr
I suppose I could try to have the Mac create and format a partition but I don't like that plan so much. Reason: I have a hunch that current version of GParted is better than an 8 year old version of Disk Utility. If behind the scenes, Disk Utility is using Bash, then that would be the logical conclusion because I read that cira 2016 Mac OS is running a Bash version circa 2007. Then again, maybe Disk Utility works around that. So, uneducated speculation on my part.

Also, I have not had good fortune with Disk Utility. For example,

Thumb drive formatting attempt results in error

MacBook Air 2017 I have a USB thumb drive that I plan to turn into a Mac OS Sierra bootable installer. The MacBook Air had trouble formatting the drive. After taking too long, Disk Utility gave an error. 1) I am surprised that I even need to format the drive. Can't Mac OS just write the...

forums.macrumors.com

Unable to format a drive: Disk Utility Couldn't open disk -69879

MacBook Air 2017 Mac OS Monterey I connected an HDD to my MacBook Air using a Sata to USB 2.0 cable. The HDD had a bootable Windows 10 or Windows 7 install on it. The drive had sat for a looong time without power (maybe 3 years). The 2 partitions for this HDD were visible on my desktop. The...

forums.macrumors.com

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The caveat with using the Linux machine to create the partition is that creating an APFS partition in GParted (on Linux) might not be straightforward.

So, I am leaning towards creating an exFat or HFS+ partition. Then, maybe Mac OS will then need to format the partition again.

Thoughts?

 

[Harddrive]

I still use separate drives for all my OS's one for OS26, one for Win 11 and one for Ubuntu 26.04 that way no errors or mishaps since all 3 use a different language to back up. Tried using a large DAS in the past partioned and formatted for each OS and for the most part it worked sometimes outside of back up failed or an error occurred so after having completely separate drives for each that problem or problems went away .

 

[rib00]

...partioned and formatted for each OS and for the most part it worked sometimes outside of back up failed or an error occurred so after having completely separate drives for each that problem or problems went away .

I think I am going to risk it.
But, it's good to know that I am running a risk - and to be on the alert.

 

[!!!]

Reason: I have a hunch that current version of GParted is better than an 8 year old version of Disk Utility

I don't see how GUID would have changed in 8 years to make DU outdated, but I would use gparted for editing the partition table anyways, since you're dealing with linux partitions macOS doesn't understand. If you're asking about formatting as HFS, I would definitely recommend you use DU, it's made by Apple, the same people who defined the HFS spec.

If behind the scenes, Disk Utility is using Bash, then that would be the logical conclusion because I read that cira 2016 Mac OS is running a Bash version circa 2007

Disk Utility is its own thing and does not use bash in any way.

 

[adrianlondon]

Another option is to leave your HDD connected to your Linux box and configure it to accept Time Machine backups over the LAN.

Configure SMB on your Linux box, and create then share a directory on your HDD. You can limit the size of the Time Machine backup in the smb.conf file. There's some basic info here: https://wiki.samba.org/index.php/Configure_Samba_to_Work_Better_with_Mac_OS_X

Then on your Mac, you simply add the new samba share. If you've configured it properly on your Linux box, it'll already be advertised as a valid TM destination and show up when you go to add a new TM destination on your Mac.

I have an old 2013 Macbook Pro which now runs Ubuntu. I use its internal SSD for Time Machine backups from my current Macbook. I also back up to a local USB drive occasionally, as obviously I need the old Macbook to work for it to accept the backups.

 

[rib00]

...I would use gparted for editing the partition table.... If you're asking about formatting as HFS, I would definitely recommend you use DU, it's made by Apple, the same people who defined the HFS spec.

Thank you. To create the partition table, I assume that you mean actually creating a partition on the Linux machine (as that seems like an easy way to edit the partition table).
I didn't realize that Time Machine wants HFS+. I just read up on that and you are right.

Another option is to leave your HDD connected to your Linux box and configure it to accept Time Machine backups over the LAN.
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I have an old 2013 Macbook Pro which now runs Ubuntu. I use its internal SSD for Time Machine backups from my current Macbook. I also back up to a local USB drive occasionally, as obviously I need the old Macbook to work for it to accept the backups.

Thank you. I didn't think of the shared folder idea.
That is also something to have in my toolbox for laptops/ small form factor computers in which the "pain" of removing the drive and the cost of the adapter are a burden. I'd imagine that some drives can't even be removed so useful there, too.
Do you think it might be more reliable from a computing perspective? !!! (username) had mentioned some technical issues with the shared drive.
I am leaning towards just moving the drive back and forth for simplicity reasons.

 

[adrianlondon]

Moving the drive back and forth is easier. Also, it doesn't matter then whether your Linux box is in a working order or not.

If my old Macbook dies, or I somehow mess up by Ubuntu install, then I won't be able to use its internal SSD for TM backups. However, I like to tinker, so that's why I did it this way. As I say, I also have a USB drive which is MacOS formatted and used for TM and manual backups.

 

[chown33]

Have you tried making a disk image using Disk Utility?
If the Linux box doesn't need access to the disk image contents, and only Macs do, this could work.

I recommend the "sparse bundle" format.

I don't know if your TM version will decline to use a disk-image, but it used to accept them.

 

[gilby101]

So, I am leaning towards creating an exFat or HFS+ partition. Then, maybe Mac OS will then need to format the partition again.

1) Backup your Linux partitions (just in case). Make sure you know how to recover your Linux configuration in case you have to repartition with Disk Utility.
2) You do need the Partition Map to be GUID. It likely is, but check.
3) It probably doesn't matter where you do the partitioning. But you may need to erase and repartition in Disk Utility.
4) Format the TM partition using macOS Disk Utility as HFS+.
5) Initiate TM and let it do the first backup.

I am sure you can make this work, but it is not something to be recommended.

You may know this already: Time Machine uses hard linked directories as well as hard linked files. Your Linux may not understand hard linked directories. So be careful accessing the TM partition from Linux.