====== ZFS Failed Disk Replacement ======

**Hot Spares**: https://docs.oracle.com/cd/E19120-01/open.solaris/817-2271/gcvcw/index.html

**Hot Spares**: https://docs.oracle.com/cd/E53394_01/html/E54801/gpegp.html

https://docs.joyent.com/private-cloud/troubleshooting/disk-replacement

http://docs.oracle.com/cd/E19253-01/819-5461/gbcet/index.html

http://docs.oracle.com/cd/E19082-01/817-2271/ghzvx/index.html

<note important>Identify the problem drive and location **exactly** before replacing!</note>

<note tip>**Power the server off when manipulating disk drives**, if at all possible.  This can go a long way towards eliminating self inflicted wounds!</note>

<note tip>The normal replacement procedure involves fixing the pool first, then removing the failed drive. Replace in-place if you must.</note>

===== Napp-IT =====

Replace with spare:

**Degraded -> Offline -> Replace**

Replace in-place drive:

**Degraded -> Offline -> Remove -> Pull Bad Drive -> Install New Drive -> Initialize -> Add to VDEV**

Wait for the **resilvering** to finish then run a **scrub** job.

===== CLI =====

==== Replace a Failed Drive ====

https://www.thegeekdiary.com/solaris-zfs-how-to-offline-online-detach-replace-device-in-a-storage-pool/

<note tip>Use ''zpool replace'' to replace a failed drive.  It is safest to replace a failed drive with another existent drive **in another slot**.</note>

<file>
zpool replace <poolname> <faileddisk> <newdisk>
</file>

<note tip>To replace a failed drive by replacing it **in-place**, it is best to shut down the server, remove and replace the failed drive, then use ''zpool replace'' specifying only the drive being replaced.</note>

<file>
zpool replace <poolname> <disk>
</file>

<note tip>After initializing a new replacement drive in-place using Napp-IT on OmniOS, this is the command that Napp-IT uses when replacing a drive.
</note>

<file>
zpool replace -f "poolname" c0t5000C500418A83B3d0 c0t5000C500836A90C7d0
</file>

<note tip>''zpool detach'' will remove a drive from a VDEV, turning a mirrored VDEV into a single drive VDEV.  Use ''zpool attach'' to recreate the mirror.  In general, **do not use these commands to replace a failed drive**.</note>

==== Replace Old Drives With New or Bigger ====

https://www.thegeekdiary.com/solaris-zfs-how-to-offline-online-detach-replace-device-in-a-storage-pool/

<note tip>It is safest to ''zpool attach'' an additional mirror to a mirrored VDEV (which adds redundancy) then remove the drive being upgraded afterwards.</note>

<file>
zpool attach <poolname> <existingvdevmember> <newdrive>
# Wait for it to resilver, which adds redundancy, then
zpool detach <poolname> <drivebeingreplaced>
</file>

==== Spares ====

Usually a spare can replace a faulted disk but **remains a spare**.  The idea behind this is that you replace the faulted disk, then replace the spare with the new and the spare remains a spare.

If you want to remove the spare property, first remove then replace.

===== Pool Expansion =====

https://tomasz.korwel.net/2014/01/03/growing-zfs-pool/

https://docs.oracle.com/cd/E36784_01/html/E36835/gazgm.html

==== CLI ====

<note tip>You can expand a ZFS pool by replacing redundant drives on replacing them **one at a time**.  **Be sure to wait for the resilvering to finish before replacing the next drive!**</note>

<note tip>Shut down the server to physically replace drives. If you have hotswap capability, you can use ''zpool offline <poolname> <disk>'' to tell ZFS to ignore the device being replaced.</note>

<file>
# Set the autoexpand property so the new disk space is recognized
zpool set autoexpand=on <poolname>
# Verify everything is online before replacing a disk
zpool status
# Take the old, smaller disk offline before removing it
zpool offline <poolname> <olddisk>
##### Physically replace the disk with the new larger disk #####
zpool online <poolname> <samediskname>
# Optionally kick off the autoexpand of each new larger device
zpool online -e <poolname> <device>
</file>