Weird feature flag appearing on pool without being added

OpenZFS
1

I’m setting up another bare-metal server at OVH, something I’ve done many times before. My process is to boot the machine using their ‘rescue’ image (which is based on Debian 12 and has ZFS support built-in). Using an SSH connection I then go through the process of setting up disk partitions, creating a root pool, installing Debian 13 (with ZFS) into it, etc. Once that is all done I reboot the machine from the hard disks and it’s up and running.

When trying to boot this machine, the initramfs fails to import the root pool, claiming that a feature flag named com.truenas:block_cloning_endian is enabled on the pool and is not supported. Running zpool import -o readonly=on rpool followed by zpool get all rpool shows that feature flag as active (along with two other unsupported flags as inactive).

If I reboot into the rescue system and run the same commands, these unsupported feature flags do not appear.

Has anyone seen anything like this before?

2

Ahh… in rescue mode zpool get all rpool does show a feature called block_cloning_endian, so I suspect the ZFS installation in the rescue system has some patches for additional features.

3

OK, I see it now. The rescue system has OpenZFS 2.4, and Debian 13 has OpenZFS 2.3. I’ll recreate the pool using the OpenZFS 2.3 ‘compatibility’ feature set.

2 Likes
4

Thanks for documenting this here, even though you found your own answer!

2 Likes
5

Stable Backports has 2.4.x - so you should be able to upgrade and use all the features as well. Just putting it out here in case it helps.