The chapter 9.5 https://www.ixsystems.com/documentation/freenas/11.2/storage.html#replacing-a-failed-disk doesn't really descrive the actions what to do when you had a spare disc in the system, and once a pool degraded, the spare was taken automatically and the resilvering is done and completed.
Points to clarify:
- what to do with "zpool status" output of the sort:
spare-9 DEGRADED 0 0 0
6936645813021573838 OFFLINE 6 187 0 was /dev/gptid/5746b895-bb3f-11e8-b48e-002590d36b60
4397662677974785947 INUSE was /dev/gptid/7b863443-bb3f-11e8-b48e-002590d36b60
- how to identify WHICH disk was failed, and, if the server has an external enclosure, in which enclosure it was?