1 Currently unreadable (pending) sectors

[MrDragonsEye]

Hi, The other day, my NAS reported the following Critical alert:
CRITICAL: 26 Nov 2017, 7:33 a.m. - Device: /dev/ada1, 1 Currently unreadable (pending) sectors
Because it's just one bad sector on one of the 4 drives, I am still able to access my data and I noticed it rebuilding or moving data around the other day to compensate or work around this which I was made aware of before I tried to reboot it in the middle of this operation.

I've been doing some research on this error and have found differing results and steps to follow. I ran a SMART test the other day which completed overnight and has reported:

SMART Self-test log structure revision number 1
Num Test_Description Status Remaining LifeTime(hours) LBA_of_first_error
# 1 Extended offline Completed without error 00% 10671 -

I was origonally trying to follow this guide: http://bytesandbolts.com/fixing-freenas-error-currently-unreadable-pending-sectors/

Any advice would be greatly appreciated and I can provide systems details and command results if it would help.

 

[danb35]

This question seems to come up a few times a week; even a brief review of this forum (never mind an actual search) should have found a number of threads. But start here: https://forums.freenas.org/index.ph...bleshooting-guide-all-versions-of-freenas.17/

 

[Jailer]

If it passes a long SMART test with just 1 pending sector I wouldn't worry too much about it. Just keep an eye on it and if it gets worse or it fails a SMART test replace it.

 

[MrDragonsEye]

Thanks for the suggestions. I've run a second long smart test and got the following back:

SMART Self-test log structure revision number 1
Num Test_Description Status Remaining LifeTime(hours) LBA_of_first_error
# 1 Extended offline Completed: read failure 90% 10685 2817680824
# 2 Extended offline Completed without error 00% 10671 -

After reading some other threads, it looks like I can ignore it for now, hide the alert and if there are any more bad sectors in the future, replace the drive.
I haven't tried rebooting the NAS yet but have setup a Long S.M.A.R.T test in the scheduler because I only had a short test in there previously.

 

[danb35]

After reading some other threads, it looks like I can ignore it for now

If it's failing a SMART test (and it is), I'd consider the drive faulty and replace it.

 

[MrDragonsEye]

Thanks @danb35
Been reading some more threads regarding this and the other critical alert I've just got:

Code:

28 Nov 2017, 2:18 p.m. - Device: /dev/ada1, Self-Test Log error count increased from 1 to 2

And it looks like it might qualify for an RMA.
I will contact WD and see what they say.

 

[Johnnie Black]

And it looks like it might quality for an RMA.

A single pending sector or a failing SMART test are enough for an RMA.

 

[Jailer]

Just chiming to agree with the others, RMA that drive.

 

[joeschmuck]

I'm sorry, I am having a tuff day when I see someone post so little of the SMART output. You are tying our hands and are not giving us the entire picture, I just don't understand it. If you don't want the serial number out for everyone to read then remove all but the last three digits this way we can at least identify the drive by part of the serial number. Until I see all fo the output from smartctl -a /dev/ada1 it is difficult to give you 100% correct advice.

With that said I do agree with my fellow forum friends, this drive looks like an RMA is in it's immediate future if it's within the warranty period.

I will contact WD and see what they say.

WD has a very easy online form to fill out and you can do an Advanced RMA where they will ship you a replacement provided you give them a Credit Card just in case you don't ship back the suspect drive. In addition you ship back the suspect drive in the same box the new-to-you drive comes in and they have a postage paid return label. You can't beat it.