Recovering ZFS Pool
Once in a while, more so after doing major system upgrades, you might end up losing your ZFS pool due to unknown circumstances. In this post I’ll talk about how you can easily recover your pool. Your / partition should NOT be on ZFS pool.
So the other day I was upgrading my workstation from Fedora 22 to Fedora 23 and after the upgrade my ZFS pool disappeared! Oh BTW, I’m using ZoL(ZFS on Linux).
Troubleshooting
Normally the command zpool status
would display detailed health status for the specified pool. But, if your pool is missing then you’ll get something like:
root@localhost ~ # zpool list
no pools available
root@localhost ~ # zpool status
no pools available
Scary, right??
Quick Fix
Using zpool import
we’ll list all pools available & then import them.
zpool import [-d dir | -c cachefile] [-D] Lists pools available to import. If the -d option is not specified, this command searches for devices in “/dev”.
List all pools
root@localhost ~ # zpool import pool: tank id: 11742341043733316809 state: ONLINE action: The pool can be imported using its name or numeric identifier. config: tank ONLINE raidz1-0 ONLINE ata-WDC_WD30EFRX-68EUZN0_WD-WMC4N0824448-part1 ONLINE ata-WDC_WD30EFRX-68EUZN0_WD-WMC4N0824448-part2 ONLINE ata-WDC_WD30EFRX-68EUZN0_WD-WMC4N0824448-part3 ONLINE ata-WDC_WD30EFRX-68EUZN0_WD-WMC4N0824448-part4 ONLINE 11742341043733316809 ONLINE
Finally, import your pool, in this case, tank
root@localhost ~ # zpool import tank
All is well after all! No data lost :)
root@localhost ~ # zpool status pool: tank state: ONLINE scan: scrub canceled on Tue Oct 27 08:15:07 2015 config: NAME STATE READ WRITE CKSUM tank ONLINE 0 0 0 raidz1-0 ONLINE 0 0 0 ata-WDC_WD30EFRX-68EUZN0_WD-WMC4N0824448-part1 ONLINE 0 0 0 ata-WDC_WD30EFRX-68EUZN0_WD-WMC4N0824448-part2 ONLINE 0 0 0 ata-WDC_WD30EFRX-68EUZN0_WD-WMC4N0824448-part3 ONLINE 0 0 0 ata-WDC_WD30EFRX-68EUZN0_WD-WMC4N0824448-part4 ONLINE 0 0 0 11742341043733316809 ONLINE 0 0 0 errors: No known data errors root@localhost ~ # zpool list NAME SIZE ALLOC FREE EXPANDSZ FRAG CAP DEDUP HEALTH ALTROOT tank 2.44T 143G 2.30T - 5% 5% 1.07x ONLINE - root@localhost ~ # zfs list NAME USED AVAIL REFER MOUNTPOINT tank 123G 1.77T 166K /mnt/zpool/tank tank/backups 117G 383G 117G /mnt/zpool/tank/backups tank/deadhorse 4.34G 496G 4.34G /mnt/zpool/tank/deadhorse