I have been playing around with chmod, chown, setfacl and special bits trying to get multiple system/full users in same group correct access permissions to my media collection.

But I’ve messed it up somehow and now I’m having weird problems that are hard to track.

I would like to set my whole collection back to the defaults.

What is the best way to do this?

One problem I’ve had when making changes to so many files is the process seems to go forever without completing. Eventually it gets killed so my filesystem has variable attributes throughout. how can this be worked around?

I want everything to be owned by myuser, group media, everything else default I will sort it from there once I have a fresh slate.

And is there a way to backup these attributes only? I don’t have enough storage to backup the files themselves.

It is Debian with ext4 filesystem.

Edit to add: Media collection is on its own separate drive/filesystem; this has no impact on anything else on the computer.

  • mina86@lemmy.wtfEnglish
    3·
    12 hours ago

    As root:

    cd /filesystem/in/question
chown myuser:media -R /filesystem/in/question
find -exec chacl -B -- {} +
find -exec chmod 644 -- {} +
find -type d -exec chmod 755 -- {} +
    • layzerjeyt@lemmy.dbzer0.comOP
      2·
      12 hours ago

      I’m not familiar with chacl (“change the access control list of a file or directory”). Is is similar to setfacl (“set file access control lists”)? A matter of preference/habit?

      It seems like -B does “Remove all ACLs”. Which I guess is what I am asking for? Files on linux are OK to have no ACLs?

      About the find ... {} +, I see {} +

      runs the specified command on the selected files, but the command line is built by appending each selected file name at the end; the total number of invocations of the command will be much less than the number of matched files.

      So does it wait until it has found all the matches to run the command as a giant batch instead of running it as it finds matches?

      • insufferableninja@sh.itjust.worksEnglish
        3·
        11 hours ago

        chacl is from IRIX, and is included for backward compatibility afaik. setfacl is the more common command.

        setfacl -b is the same as chacl -B IIRC

      • ReversalHatchery@beehaw.org
        3·
        10 hours ago

        So does it wait until it has found all the matches to run the command as a giant batch instead of running it as it finds matches?

        almost. it runs the command in batches, if you have few enough files it may only run it once. this shouldn’t make it slower, but actually faster.

        and yes, linux does not use ACLs by default. on ext4 usage of ACLs is not even enabled by default, but only if you set it up with the right mount option

        • layzerjeyt@lemmy.dbzer0.comOPEnglish
          1·
          11 hours ago

          on ext4 usage of ACLs is not even enabled by default

          Is that the case? One reason I included the information is because I found conflicting info and I am unsure. I specifically recall reading it is default on ext4 but not ext3.

          archwiki:

          acl is specified as a default mount option when creating an ext2/3/4 filesystem

          This SE thread has a coment dated 2015:

          Recent distro have ACL mount option included by default (since kernel 2.6). So it’s not mandatory to redefine it in /etc/fstab (or similar). Non exhaustive list of filesystems concerned: ext3, ext4, tmpfs, xfs and zfs .

          I don’t think I have read anywhere it is not default for ext4, only for earlier exts.

          • ReversalHatchery@beehaw.org
            2·
            10 hours ago

            oh, that’s right, sorry. it must have changed in recent years.

            so I haven’t either found a definitive answer to whether it is a default mount option, but the closest I found is almost it: man mount says to look in man ext4, and there itsays the defaults are determined by the filesystem superblock.

            the superblock’s settings can be viewed with tune2fs -l /dev/your_blockdev, and according to the “default mount options” line I indeed have acl enabled by default on all my ext4 filesystems.

            so in the end, the default is determined by the tool that makes the filesystem. mkfs.ext4 reads them from /etc/mke2fs.conf if not overridden with an argument. on my system tue acl option is right there in this file.

            and that also means that this depends not on your current system, but on the system where the filesystem was created.

      • mina86@lemmy.wtf
        2·
        11 hours ago

        So does it wait until it has found all the matches to run the command as a giant batch instead of running it as it finds matches?

        Indeed. If possible, it is typically what you want (as opposed to find ... -exec ... {} \; which runs command for each found file) since it will run faster. You want find ... -exec ... {} \; if the command you’re executing can run on single file only or you’re dealing with legacy system without -exec ... {} + support.