1 Reply Latest reply on Jul 1, 2020 9:34 PM by Nik

    Can I use zfs snapshot for patching, for purpose of backup?




      I have Solaris 10 x86 physical server, running 17 non-global zones on it. I need to install the recommended patch cluster. I can't use live upgrade because every zone has separate /var. LU has its limitation that /var should be part of root.

      Hard disk is configured in hardware RAID-5, so I can't split the mirror and patch just one side of mirror.

      Another option I can think of, using ZFS snapshot. But I never used it.

      In case, I need to revert back to old environment (non-patched), can I use ZFS snapshots easily? I tried to google steps for this, but not able to see any relevant document.



      Otherwise, I need to change design of this server and merge /var into root of all 17 zones and then use live upgrade, which is time-consuming.




        • 1. Re: Can I use zfs snapshot for patching, for purpose of backup?


          LU on ZFS use snapshots for create new BE, so  You can  use snapshots for store current state but ....

             Snapshots is not backup, becouse not covered all cases.

            Some examples when snapshots not help:

              - ZFS pool is courrupted. ( Or you lost  2 or more disks on Your raid 5).

              - You  upgrade zpool after patching.  Old kernel can not use  new version of pool.

            So You should have  backup on other media in any case.



          In case You will try use snapshot:

             - Check free spaces on  zpool.


          For retrun to initial state you can use:

            -  rollback FS to snapshot  ( not recommend, becouse You lost patched state)


          -  create clone FS from snapshot.

                 After this  you should substitue  mount point  for  new cloned FS.

                 May be need change configuration of zones ( I do not know how /var mounted at zone)

                 need change properties of rpool (specify bootfs )