Clearing Transient or Persistent Device Errors

If the device errors are deemed transient, in that they are unlikely to affect the future health of the device, they can be safely cleared to indicate that no fatal error occurred. To clear error counters for RAID-Z or mirrored devices, use the zpool clear command. For example:

$ zpool clear system1 c1t1d0

This syntax clears any device errors and clears any data error counts associated with the device.

To clear all errors associated with the virtual devices in a pool, and to clear any data error counts associated with the pool, use the following syntax:

$ zpool clear system1

For more information about clearing pool errors, see Clearing Storage Pool Device Errors.

Transient device errors are most likely cleared by using the zpool clear command. If a device has failed, then see the next section about replacing a device. If a redundant device was accidentally overwritten or was UNAVAIL for a long period of time, then this error might need to be resolved by using the fmadm repaired command as directed in the zpool status output. For example:

$ zpool status -v pond
pool: pond
state: DEGRADED
status: One or more devices are unavailable in response to persistent errors.
Sufficient replicas exist for the pool to continue functioning in a
degraded state.
action: Determine if the device needs to be replaced, and clear the errors
using 'zpool clear' or 'fmadm repaired', or replace the device
with 'zpool replace'.
scan: scrub repaired 0 in 0h0m with 0 errors on Wed Jun 20 15:38:08 2012
config:

NAME                   STATE     READ WRITE CKSUM
pond                   DEGRADED     0     0     0
mirror-0               DEGRADED     0     0     0
c0t5000C500335F95E3d0  ONLINE       0     0     0
c0t5000C500335F907Fd0  UNAVAIL      0     0     0
mirror-1               ONLINE       0     0     0
c0t5000C500335BD117d0  ONLINE       0     0     0
c0t5000C500335DC60Fd0  ONLINE       0     0     0

device details:

c0t5000C500335F907Fd0    UNAVAIL          cannot open
status: ZFS detected errors on this device.
The device was missing.
see: http://support.oracle.com/msg/ZFS-8000-LR for recovery


errors: No known data errors