MDADM or ZFS, EXT4 or BTRFS

    • OMV 4.x
    • MDADM or ZFS, EXT4 or BTRFS

      Hey guys,
      I'm in the process of building a new NAS using OMV but there are just so many option available. Which is a blessing and a curse :)

      Server has 12x 8TB drives, and 128gb Ram.

      I've been tossing up between MDADM and ZFS.
      I think I'm going to use MDADM as its built in and well supported.
      Are there any performance differences?
      Does MDADM stripe data across drives like ZFS so it'll read and write to all drives?

      Lastly FS, EXT4 or BTRFS?
      I know EXT4 is the old tried and true, but I'm kinda worried about bitrot and other issues.
      I like where BTRFS is going and think this will be a good solution, any advice?
      Lastly does OMV make use of the BTRFS added features?

      Thanks all
    • +1 to ZFS is robust and have better resilver speed, and you can create a pool in one minute ( MDADM need several days to complete initialize).
      of course have more advantages.

      Please google a bit and read comparatives
      OMV 4.1.11 x64 on a HP T510, 16GB CF as Boot Disk & 32GB SSD 2,5" disk for Data, 4 GB RAM, CPU VIA EDEN X2 U4200 is x64 at 1GHz

      Post: HPT510 SlimNAS ; HOWTO Install Pi-Hole ; HOWTO install MLDonkey ; HOHTO Install ZFS-Plugin ; OMV_OldGUI ; ShellinaBOX ; ctop
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    • savellm wrote:

      I've been tossing up between MDADM and ZFS.
      /-----/Lastly FS, EXT4 or BTRFS?
      I agree with @raulfg3 .

      While ZFS supports RAID like striping, it is also a file system. It does RAID like drive aggregation, LVM, and file system functions combined.
      If you're truly worried about bit-rot, mdadm won't do a thing for you. One of the best approaches, for bit-rot, is ZFS using a pool of zmirror vdev's. It's easy to set up.

      The post was edited 1 time, last by crashtest ().

    • Thats part of the problem, ive read so much I now just confusing myself.
      I also dont really see a good comparison between everything.

      Lastly I heard that ZFS wasnt well maintained on OMV.
      And things like snapshots and so on dont work, or dont work in the GUI.

      This is the reason for all my questions.
      Is the general consensus that people use ZFS?

      If so why doesnt it get included and better maintained in OMV?
    • savellm wrote:

      If so why doesnt it get included and better maintained in OMV?
      For legal reasons since the ZFS license is not compatible with the GPL Linux/Debian relies on. So ZFS can't be shipped as part of OMV's core and as such can only be supported via a plugin. And you need to become a bit familiar with maintenance basics and should always test stuff before relying on it, see e.g. Replacing a defective disc in a ZFS pool

      Since you did an opinion poll here's another one for ZFS.
      No more contributions to this project until 'alternative facts' (AKA ignorance/stupidity) are gone
    • What about using OpenZFS?

      But thanks, this really makes me rethink and I'm going to retest :)
      Really appreciate all these comments.

      Will there get better maintenance of ZFS? IE more GUI options like resliver and so on?
      If I do ZFS (I was testing FreeNAS) does it have all the auto snapshots and so on?
      Or does that need to be manually setup or is it not supported?
    • savellm wrote:

      What about using OpenZFS?
      Just do a web search for it. OpenZFS is the basis of ZoL that is used here. But this doesn't change a bit wrt the licensing situation.

      There is no need for resilver GUI options since a resilver will start automatically once you replaced a disk (zfs replace) or bring it back online (zfs online). But basic maintenance in case of troubles has to happen on the command line (even if a plugin would allow such stuff via GUI I wouldn't trust in since if you replace the wrong disk your whole array/pool might be lost).

      For snapshots I would recommend looking into ZnapZend (3rd party tool) since this allows for full backup functionality with another host also using ZFS. And yes, Proxmox kernel is a good idea to use since this is more or less Ubuntu's upstream stable kernel so no need for compilation orgies as ZFS is already built-in.
      No more contributions to this project until 'alternative facts' (AKA ignorance/stupidity) are gone
    • Compilation orgies made me lol.
      So I didnt do the kernel first and charged in to install zfs plugin:

      Source Code

      1. Building initial module for 4.19.0-0.bpo.5-amd64
      2. configure: error:
      3. *** Please make sure the kmod spl devel <kernel> package for your
      4. *** distribution is installed then try again. If that fails you
      5. *** can specify the location of the spl objects with the
      6. *** '--with-spl-obj=PATH' option. Failed to find spl_config.h in
      7. *** any of the following:
      8. /usr/src/spl-0.7.12/4.19.0-0.bpo.5-amd64
      9. /usr/src/spl-0.7.12
      10. Error! Bad return status for module build on kernel: 4.19.0-0.bpo.5-amd64 (x86_64)
      11. Consult /var/lib/dkms/zfs/0.7.12/build/make.log for more information.
      12. Processing triggers for openmediavault (4.1.22-1) ...
      13. Restarting engine daemon ...
      14. Setting up linux-headers-4.19.0-0.bpo.5-common (4.19.37-3~bpo9+1) ...
      15. Setting up libzpool2linux (0.7.12-1~bpo9+1) ...
      16. Setting up linux-headers-4.19.0-0.bpo.5-amd64 (4.19.37-3~bpo9+1) ...
      17. /etc/kernel/header_postinst.d/dkms:
      18. cp: cannot stat '/var/lib/dkms/spl/0.7.12/build/spl_config.h': No such file or directory
      19. cp: cannot stat '/var/lib/dkms/spl/0.7.12/build/module/Module.symvers': No such file or directory
      Display All
      And its been stuck here for 10mins. I'll let it run but seems dead.
      Will trying again. Do I need to do proxmox kernel first then install plugin?