Any way to create new pool with downlevel ZFS features (for potential rollback)

[djjaeger82]

Hi all,
I'm running 12.0-U1.1, but I was hit with the data corruption bug prior to the U1.1 fix which screwed up some of my WHS 2011 client computer backup database files. I'm in the midst of upgrading my storage after recovering from my data loss / corruption, and I'm building a new 4x18TB RaidZ-1 array. While 12.0U1.1 has been stable for me so far (over a week+ now), I'd still like to leave my options open in case I have to rollback to 11.x in the future.

Is there anyway if I'm creating a new pool with 12.x to build the pool with a down level feature set so that rollback to an older Freenas/Truenas build would be possible?

 

[Yorick]

4x18TB RaidZ-1

Brave. Backup storage only, is that right?

build the pool with a down level feature set

For now, you have to manage this by hand on CLI. Create your pools with -d and then -o feature@NAME=enabled for each feature you want to enable. Pick the list of features so you can roll back.

An easier option may be to boot into 11.3, create the pool, then boot into 12.0 and not upgrade pool features.

 

[djjaeger82]

An easier option may be to boot into 11.3, create the pool, then boot into 12.0 and not upgrade pool features.

I'm thinking about doing exactly this, since specifying feature by feature is going to be a PITA (and i'm not familiar with all the individual feature sets that changed from 11.x to 12.x). Already started populating the data onto the version 12 pool, but only about 30min into it, so if I'm going to change now would be the time. Whats the odds Truenas massively screws up again with a data corrupting but when they re-implement CoW on 12.0-U3?

 

[Chris Moore]

You could install an older version of FreeNAS on separate media, boot from it, create the pool, then shutdown and switch back to the regular boot media to import the new/old pool. Nothing saying it must be upgraded. Then copy pool to pool.