Tag Archives: zfs

ZFS replace disk

I’m using ZFS for my main fileserver, this pool was created over 10 years ago.
Meanwhile i’ve: Swapped broken disks, switched disks for bigger ones and effectively resized my storage 2 or 3 times. Never had any corruption.

Yesterday i say a warning that one of the disks in the pool was OFFLINE.
Today i replaced it using below command’s

  • Put the disk in OFFLINE mode (if needed, mine was already offline)
    • zpool offline tank sdb
  • Remove disk from system
    • echo 1 | sudo tee /sys/block/sdb/device/delete
  • Remove the disk physically
  • Insert the replacement disk. And copy headers/structure from another disk
    • sgdisk –replicate=/dev/sdb /dev/sda
    • sgdisk –randomize-guids /dev/sdb
  • Run the zpool replace command. 
    • zpool replace tank /dev/sdb
  • Use online command to activate disk (no needed in my case, it already did that)
Tips:

# My labels with serials fell off :(
dd if=/dev/sdb of=/dev/null -> blinky led .. 

# What is the serial?
sudo hdparm -i /dev/sdb | grep Serial

Output

root@latex:~# sgdisk --replicate=/dev/sdb /dev/sda
The operation has completed successfully.
root@latex:~# sgdisk --randomize-guids /dev/sdb
The operation has completed successfully.
root@latex:~# zpool replace tank /dev/sdb
root@latex:~# zpool status
  pool: tank
 state: DEGRADED
status: One or more devices is currently being resilvered.  The pool will
        continue to function, possibly in a degraded state.
action: Wait for the resilver to complete.
  scan: resilver in progress since Wed May 18 11:31:21 2022
    5.64T scanned out of 14.4T at 331M/s, 7h42m to go
    1.88T resilvered, 39.16% done
config:

        NAME             STATE     READ WRITE CKSUM
        tank             DEGRADED     0     0     0
          raidz1-0       DEGRADED     0     0     0
            sda          ONLINE       0     0     0
            replacing-1  REMOVED      0     0     0
              old        REMOVED      0     0     0
              sdb        ONLINE       0     0     0  (resilvering)
            sdc          ONLINE       0     0     0

errors: No known data errors