ZFS 10.2 zfs-on-root will not boot after an unclean reboot

[Ricky Huang]

Server got power-cycled by the datacenter (accident) and now it won't boot. Previous "proper" reboots have always been fine.

It's a ZFS-on-root setup installed via FreeBSD installer and it's now displaying:

FreeBSD/x86 boot
ZFS: I/O error - blocks larger than 128K are not supported
ZFS: can't find dataset u

Any suggestions on where I can begin to diagnose this issue?

Note: I have infrequent access to the server, so please "batch" the suggestions so I can try them when I make my way into the d.c.


Thanks in advance!

 

[Eric A. Borisch]

You didn't happen to use the feature@large_blocks zpool feature (by setting a record size larger than 128K) did you? From man zpool-features:

"Please note that booting from datasets that have recordsize greater than 128KB is NOT supported by the FreeBSD boot loader."

You can try booting from a FreeBSD live image and checking zpool get feature@large_blocks <pool name> to see if it is 'active' (assuming it imports for you.)

 

[Ricky Huang]

You didn't happen to use the feature@large_blocks zpool feature (by setting a record size larger than 128K) did you? From man zpool-features:

"Please note that booting from datasets that have recordsize greater than 128KB is NOT supported by the FreeBSD boot loader."

You can try booting from a FreeBSD live image and checking zpool get feature@large_blocks <pool name> to see if it is 'active' (assuming it imports for you.)

I used the default ZFS settings during the FreeBSD installer... I don't recall explicitly turning anything on.

But I will check that the next time I get to the datacenter.


Thank you.