Problem fixin Currently unreadable (pending) sectors

[jafisher2000]

Device: /dev/da0 [SAT], 8 Currently unreadable (pending) sectors. When I run smartctl -l selftest /dev/da0 I get #20 Extended offline Completed without error 00% 4431. How to fix. Thanks

 

[Johnnie Black]

If's the extended SMART test doesn't fail then the pending sectors are "false positives", you can just ignore them, but a full disk write, with dd for example, will usually clear them.

 

[jafisher2000]

Thanks for the quick reply. I have limited knowledge of Linux. How would I need to go about doing the full disk write. I have 2 6TB HDD's mirrored.

 

[Johnnie Black]

You'd need to offline the disk (that would leave the pool with no redundancy for the duration), use dd:

dd if=/dev/zero of=/dev/daX bs=4k

Then resilver the disk.

 

[Chris Moore]

Sometimes, you get many more bad sectors. Pending sectors sometimes clear up but not always. Do the extended test, that is the real test of the drive. A short test doesn't inspect the surface of the disk the way a long test does.

 

[Chris Moore]

Hard Drive Troubleshooting Guide (All Versions of FreeNAS)
https://forums.freenas.org/index.ph...bleshooting-guide-all-versions-of-freenas.17/

Github repository for FreeNAS scripts, including disk burnin
https://forums.freenas.org/index.ph...for-freenas-scripts-including-disk-burnin.28/

 

[jafisher2000]

Sometimes, you get many more bad sectors. Pending sectors sometimes clear up but not always. Do the extended test, that is the real test of the drive. A short test doesn't inspect the surface of the disk the way a long test does.

If you read my post you will see that a extended test was ran

smartctl -l selftest /dev/da0 I get #20 Extended offline Completed without error 00% 4431

 

[Chris Moore]

If you read my post you will see that a extended test was ran

Completely not the point. Sometimes bad sectors are just bad sectors and there is no fixing it, it just gets worse. The drive may need to be replaced. Look at the troubleshooting link I provided, do some testing, and be prepared to replace the drive.