An important part of setting up a new storage array is testing how to recover from common failure scenarios. This is the procedure to replace a failed drive. Documented here for a time when I might need to use the procedure in anger. A zpool status showing the failed drive: root@thor:/home/wayne# zpool status tank pool: tank state: DEGRADED status: One or more devices are faulted in response to persistent errors. Sufficient replicas exist for the pool to continue functioning in a degraded state.