macos time machine shared drive permissions issue

Desire:

  • I have an external time machine backup drive, I'd like all my backups to be stored there through time machine.
    • computerA (Monterey) - is using the drive as a time machine backup drive
    • computerB (Monterey) - is attempting to use that external time machine backup drive on computerA


Issue:

  • using system preferences > time machine > select disk > [select] hard drive > authenticated (with my admin account to the computer)
    • error: "You do not have the necessary read, write, and append privileges on the selected network backup disk. Please connect as a different user or contact your network administrator"


Info:

  1. Back up to a shared folder with Time Machine on Mac – Apple Support (UK)
    1. using this article I was able to see the backup drive
    2. it gave the drive an option as a backup drive
    3. I even added my user account to the shared interface with read/write access.
  2. before macOS server was discontinued I was able to do this and still can on the macOS server now with Monterey.
    1. you could store all your backups on an external drive.
    2. looking at the permissions this drive I have "0 drwxrwxr-x  14 root  admin  544 Sep 30 10:08 Backup"
      1. do I have to change the ownership of the hard drive to admin group to make this work?
      2. the backup folder on the drive does have "0 drwxrwx---+ 6 root         admin     204 Apr 29  2022 Backups.backupdb"
  3. Permissions: I did notice
    1. 0 drwxrwxr-x@  9 root    wheel   288 Sep 30 09:10 Backup
    2. so clearly the user account was not in this wheel group


Question:

  • How can I use the 1 external time machine backup drive with multiple computers?




Posted on Sep 30, 2023 10:02 AM

Reply
4 replies

Oct 1, 2023 6:46 AM in response to SU

Using one backup drive for multiple computers is an exceedingly bad idea. Lose that one drive and you lose all backups. A single small glitch and lose all data.


Each computer needs its own dedicated backup drive. HDDs cost pocket change now days and it's "penny wise but pound foolish" to not have one for each computer.


If your data is worth securing, do it so that each computer's contents are protected separately.


Oct 2, 2023 1:05 PM in response to ku4hx

All servers would say otherwise. One drive doesn't necessary mean a single drive. But a logical volume represented as one drive.


Sorry they do not need a dedicated backup drive.


That said I'm still trying to utilize the capability that was taken away from macOS server.

Oct 4, 2023 4:23 AM in response to ku4hx

Well, actually trying to use it the way apple intended it as well. Multiple computers one drive. Which was supported through macOS server (https://www.bresink.com/osx/300807341/Docs-en/pgs/0100-SharePoints.html) and apple time capsule (Backup disks you can use with Time Machine - Apple Support) but for reasons unclear is unable to be supported through macos now.

macos time machine shared drive permissions issue

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