Upgrade Pool zfs

[Max90]

hi everyone, since I updated freenas to truenas in July 2021 I have always had this alert to upgrade the pool:
New ZFS version or feature flags are available for pool Volume. Upgrading pools is a one-time process that can prevent rolling the system back to an earlier TrueNAS version. It is recommended to read the TrueNAS release notes and confirm you need the new ZFS feature flags before upgrading a pool.
For now I have always avoided doing it, even reading around at the time.
Do you recommend doing it or is it better to leave it like this?
Advantages and disadvantages?

I don't think I'll ever go back to Freenas ..

 

[Alecmascot]

If you will NEVER downgrade then upgrade the pool.

 

[pschatz100]

I don't really understand the feature flags and whether or not they affect performance of the system, but I tend to think that it is a good idea to stay current on such things. I update the feature flags after an update has been running stable for a month or so and don't expect to downgrade back to a previous version.

 

[winnielinnie]

I always ignore it.

I prefer to be able to have the option to import the pool into an older system (or other Linux distro that might have an older version of ZFS), at the "cost" of not getting shiny new features that I never used anyways.

 

[pschatz100]

I prefer to be able to have the option to import the pool into an older system (or other Linux distro that might have an older version of ZFS), at the "cost" of not getting shiny new features that I never used anyways.

There is a point here. I maintain an external backup, originally configured about a year ago, and I don't update the feature flags there. Precisely to preserve any options I might have if I need to move to another system. However, for my production system, I like to stay somewhat current.

 

[Max90]

There is a point here. I maintain an external backup, originally configured about a year ago, and I don't update the feature flags there. Precisely to preserve any options I might have if I need to move to another system. However, for my production system, I like to stay somewhat current.

I don't think I will switch to other systems, but to avoid at this point I would wait.

 

[Ericloewe]

There’s really no point in never upgrading, just like there’s no point in jumping at the chance to upgrade: https://www.truenas.com/community/resources/zfs-feature-flags-in-truenas.95/

 

[Patrick M. Hausen]

If you decide to upgrade your boot pool I advise to also upgrade the boot loader to be on the safe side.

Example - my backup NAS which is booting via EFI:

Code:

# find out which drives the boot pool resides on
root@freenas2[~]# zpool status boot-pool
  pool: boot-pool
[...]
NAME        STATE     READ WRITE CKSUM
    boot-pool   ONLINE       0     0     0
      mirror-0  ONLINE       0     0     0
        ada6p2  ONLINE       0     0     0
        ada7p2  ONLINE       0     0     0

# mount the EFI partitions
mkdir /mnt/ada6 /mnt/ada7
mount -t msdos /dev/ada6p1 /mnt/ada6
mount -t msdos /dev/ada7p1 /mnt/ada7

# copy the current boot loader
cp /boot/boot1.efi /mnt/ada6/efi/boot/BOOTx64.efi
cp /boot/boot1.efi /mnt/ada7/efi/boot/BOOTx64.efi

# unmount the EFI partitions
umount /mnt/ada6
umount /mnt/ada7

# clean up
rmdir /mnt/ada6 /mnt/ada7

In case your system uses legacy instead of EFI boot the whole procedure gets a lot simpler:

Code:

# update the boot loader
gpart bootcode -b /boot/pmbr -p /boot/gptzfsboot -i 1 ada6
gpart bootcode -b /boot/pmbr -p /boot/gptzfsboot -i 1 ada7

Using the wrong procedure for your system will render it unbootable! That can be fixed without a reinstall, though, by booting from a generic FreeBSD ISO and repairing the boot partitions.

 

[Ericloewe]

The boot pool is really just better left alone in the absence of a great reason to upgrade it. Those are few and far between on a boot pool.
That said, don’t forget about enabled/active. For stuff like DRAID, you can enable it all you want, it’s only activated if a DRAID vdev is added.

 

[winnielinnie]

There’s really no point in never upgrading

Double-negative. Program crash. Ended up formatting my disks to NTFS. Please advise.

 

[Ericloewe]

Join the future that's been with us since that futuristic date of... checks notes 2005? Wow.