Activating and Deactivating Hot Spares in Your Storage Pool
You activate hot spares in the following ways:
-
Manual replacement – Run the
zpool replace
command to replace a failed device. When a new device is inserted to replace the failed disk, you activate the new device by detaching the spare. -
Automatic replacement – An FMA agent detects a fault, determines spare availability, and automatically replaces the faulted device. A hot spare also replaces a device in the
UNAVAIL
state.If you set the
autoreplace
pool property toon
, the spare is automatically detached and returned to the spare pool when the new device is inserted and the online operation completes.
To deactivate a hot spare, perform one of the following actions:
-
Remove the hot spare from the storage pool.
-
Detach the hot spare after physically replacing a failed disk. See **INTERNAL XREF ERROR**.
-
Swap in another hot spare either temporarily or permanently. See **INTERNAL XREF ERROR**.
Example 4-12 Detaching a Hot Spare After the Failed Disk Is Replaced
This example assume the following configuration:
-
In
system1
'smirror-1
configuration, diskc0t5000C500335BA8C3d0
has failed. The following partial output shows the status ofmirror-1
:$ zpool status system1 . mirror-1 DEGRADED 0 0 0 c0t5000C500335BD117d0 ONLINE 0 0 0 c0t5000C500335BA8C3d0 UNAVAIL 0 0 0Failed disk
-
The pool's spare
c0t5000C500335E106Bd0
is automatically activated to replace the failed disk. -
You physically replace the failed disk with a new device
c0t5000C500335DC60Fd0
.
The example begins with reconfiguring the pool with the new device. First, you run zpool replace
to inform ZFS about the removed device. Then, if necessary, you run zpool detach
to deactivate the spare and return it to the spare pool. The example ends with displaying the status of the new configuration and performing the appropriate FMA steps for fault devices, as shown in Step 6 of How to Replace a Device in a Storage Pool.
$ zpool replace system1 c0t5000C500335BA8C3d0 $ zpool detach system1 c0t5000C500335E106Bd0 $ zpool status system1 . . mirror-1 ONLINE 0 0 0 c0t5000C500335BD117d0 ONLINE 0 0 0 c0t5000C500335DC60Fd0 ONLINE 0 0 0Replacement device spares c0t5000C500335E106Bd0 AVAIL Deactivated spare $ fmadm faulty $ fmadm repaired zfs://pool=name/vdev=guid
Example 4-13 Detaching a Failed Disk and Using the Hot Spare
Instead of a new replacement device, you can use the spare device as a permanent replacement instead. In this case, you simply detach the failed disk. If the failed disk is subsequently repaired, then you can add it to the pool as a newly designated spare.
This example uses the same assumptions as **INTERNAL XREF ERROR**.
-
The
mirror-1
configuration of the poolsystem1
is in a degraded state.$ zpool status system1 . mirror-1 DEGRADED 0 0 0 c0t5000C500335BD117d0 ONLINE 0 0 0 c0t5000C500335BA8C3d0 UNAVAIL 0 0 0Failed disk
-
The pool's spare
c0t5000C500335E106Bd0
is automatically activated to replace the failed disk.
The example begins with detaching the failed disk that has been replaced by the spare.
$ zpool detach system1 c0t5000C500335BA8C3d0 $ zpool status system1 . . mirror-1 ONLINE 0 0 0 c0t5000C500335BD117d0 ONLINE 0 0 0 c0t5000C500335E106Bd0 ONLINE 0 0 0Spare replaces failed disk errors: No known data errors
Subsequently, you add the repaired disk back to the pool as the spare device. You complete the procedure by performing the appropriate FMA steps for fault devices.
$ zpool add system1 spare c0t5000C500335BA8C3d0 $ zpool status system1 . . mirror-1 ONLINE 0 0 0 c0t5000C500335BD117d0 ONLINE 0 0 0 c0t5000C500335E106Bd0 ONLINE 0 0 0Former spare spares c0t5000C500335BA8C3d0 AVAIL Repaired disk as spare errors: No known data errors $ fmadm faulty $ fmadm repaired zfs://pool=name/vdev=guid