Help Restoring Boot Drive Mirrors

[hunter]

I have my boot drive mirrored on two nearly identical sandisk thumb drives. 1 week ago when I upgraded FreeNAS, one of the two drives on the mirror became "UNAVAIL". I unplugged the drive and plugged it in again. At that point, I was able to "attach" it to the existing mirror and resilver. But the drive marked UNAVAIL remained and I could never see how to get FreeNAS to recognize that the hardware no longer existed.

Then the next time I upgraded FreeNAS, I had a similar problem. Here is zpool status. This time I tried to remove the same thumb drive and the FreeNAS web interface stopped responding and I had to press the reboot button on the hardware. It looks like this problem is not always happening to the same thumb drive. Can anyone see how to restore the mirror --or-- how to just go back to a single drive if the mirror is not going to be reliable during reboots (so far, it has not been) ?

pool: freenas-boot
state: DEGRADED
status: One or more devices could not be opened. Sufficient replicas exist for
the pool to continue functioning in a degraded state.
action: Attach the missing device and online it using 'zpool online'.
see: http://illumos.org/msg/ZFS-8000-2Q
scan: resilvered 3.07G in 0h44m with 0 errors on Thu Feb 12 19:57:18 2015
config:

NAME STATE READ WRITE CKSUM
freenas-boot DEGRADED 0 0 0
mirror-0 DEGRADED 0 0 0
10004170420306317259 UNAVAIL 0 0 0 was /dev/da0p2
8267032784646246760 UNAVAIL 0 0 0 was /dev/da1p2
gptid/180c62b0-b315-11e4-b6e3-002590d7e3c7 ONLINE 0 0 0

errors: No known data errors

 

[dlavigne]

Have you replaced the bad thumb drive? That is the only way to fix the boot mirror.

 

[hunter]

I never believed the thumb drives were actually going bad. This happened before and I removed the thumb drive, plugged it in again, used the replace functionality to add it back into the mirror and resilver, and everything worked fine again. Even scrubs in between FreeNAS version upgrades. In fact, the only time I have ever had a problem was after doing the FreeNAS version upgrades. This latest case, where it appears the other thumb drive has failed, suggests the same. I always thought these issues are from some sort of intermittent issue with one of the USB interface failing during the upgrade process and breaking the mirror.

I tried buying a different USB thumb drive when this was happening, and switched it. But I still have the same issue appearing at the same time(s) since installing the new USB drive...

 

[zambanini]

dlavigne is wrong, sounds more like an usb issue to me.

what hw are you using?

 

[hunter]

I too, felt it's probably a USB issue. I was hoping it was just a fluke until it started happening every couple FreeNAS upgrades.
The board is a Supermicro X9SCM-F-O Lga 1155, the USB drives are SanDisk Cruiser 16Gb I believe. I use one USB port that is in the middle of the motherboard, and another port that is on the back side of the box (port also on the motherboard).

 

[Saz]

I had this issue using USB3 sockets. Moved them to USB2 sockets and no issues since.

 

[hunter]

That's a great idea Saz, I will give it a try!