getting a read error on a drive

[dobah]

Howdy,

Today I got a read error on my drive. I'll just list 3 out of many lines that my log received.

ad6: FAILURE - READ_DMA48 status=51<READY,DSC,ERROR> error=40<UNCORRECTABLE> LBA=2621807360
ad6: FAILURE - READ_DMA48 status=51<READY,DSC,ERROR> error=40<UNCORRECTABLE> LBA=2621807616
ad6: FAILURE - READ_DMA48 status=51<READY,DSC,ERROR> error=40<UNCORRECTABLE> LBA=2621807872

freenas:~# zpool status -v
pool: zfspool
state: ONLINE
status: One or more devices has experienced an unrecoverable error. An
attempt was made to correct the error. Applications are unaffected.
action: Determine if the device needs to be replaced, and clear the errors
using 'zpool clear' or replace the device with 'zpool replace'.
see: http://www.sun.com/msg/ZFS-8000-9P
scrub: none requested
config:

NAME STATE READ WRITE CKSUM
zfspool ONLINE 0 0 0
mirror ONLINE 0 0 0
ad4 ONLINE 0 0 0
ad6 ONLINE 1 0 0


My questions is how do I replace the drive in question? Is it ok to power down the system, replace the drive, power it back up, and run the following line? Should I take the drive offline now? It appears to be working for now and my replacement disk should get here in a few days. I was reading this from another topic. viewtopic.php?f=66&t=1366
zpool replace pool ad6 /dev/ada6

[raulfg3]

ad6: FAILURE - READ_DMA48 status=51<READY,DSC,ERROR> error=40<UNCORRECTABLE> LBA=2621807360
ad6: FAILURE - READ_DMA48 status=51<READY,DSC,ERROR> error=40<UNCORRECTABLE> LBA=2621807616
ad6: FAILURE - READ_DMA48 status=51<READY,DSC,ERROR> error=40<UNCORRECTABLE> LBA=2621807872

Normally this error indicate a sector problem ( Bad Disk), but sometimes is due a defective SATA CABLE or a defective sata enclosure ( a SATA enclosure to extract Disk in hot).

My questions is how do I replace the drive in question? Is it ok to power down the system, replace the drive, power it back up, and run the following line? Should I take the drive offline now? It appears to be working for now and my replacement disk should get here in a few days. I was reading this from another topic. viewtopic.php?f=66&t=1366
zpool replace pool ad6 /dev/ada6

If this is your first error, shutdown your NAS, boot fresh and do a zpool clear, and pass some SMART test to be sure what are the origen of the problem ( Disk or SATA enclosure), once you are sure, you need to do next step , replace disk with a new disk or conect the disk directly without SATA enclosure.


viewtopic.php?f=66&t=387&p=1778

[dobah]

I did a scrub on ad6. It took a while but a ton of errors popped up. Not sure I want to see that but there isn't much I can do until my new drive arrives in the mail. Should I just take the drive offline until the new one arrives?

Zpool status
-------------------------
pool: zfspool
state: ONLINE
status: One or more devices has experienced an unrecoverable error. An
attempt was made to correct the error. Applications are unaffected.
action: Determine if the device needs to be replaced, and clear the errors
using 'zpool clear' or replace the device with 'zpool replace'.
see: http://www.sun.com/msg/ZFS-8000-9P
scrub: scrub completed after 5h18m with 0 errors on Mon Nov 19 04:00:58 2012
config:

NAME STATE READ WRITE CKSUM
zfspool ONLINE 0 0 0
mirror ONLINE 0 0 0
ad4 ONLINE 0 0 0
ad6 ONLINE 43 0 0 5.25M repaired