Whilst copying data to my FreeBSD RAID1 mirror, one of the disks errored:
Jan 4 07:08:44 freenas kernel: GEOM_MIRROR: Device RAID1: provider ad0 disconnected.
Jan 4 07:08:44 freenas kernel: GEOM_MIRROR: Request failed (error=5). ad0[WRITE(offset=1632316556288, length=131072)]
Jan 4 07:08:44 freenas kernel: ad0: FAILURE - WRITE_DMA48 status=51<READY,DSC,ERROR> error=10<NID_NOT_FOUND> LBA=3188118402
I also got this error:
"geom: Not all disks connected."
ad0 had errored, leaving the RAID operating only with ad1.
The solution was posted here:
gmirror forget RAID1
gmirror status
Name Status Components
mirror/RAID1 COMPLETE ad1
gmirror remove RAID1 /dev/ad0
gmirror: No such provider: ad0.
gmirror insert RAID1 /dev/ad0
gmirror status
Name Status Components
mirror/RAID1 DEGRADED ad1 ad0 (0%)