unreadable (pending) sectors

[massmux]

Hello i am getting these errors in a very new 10 disk freenas.

Mar 24 18:48:13 stor134 smartd[2679]: Device: /dev/ada4, 40 Currently unreadable (pending) sectors
Mar 24 19:18:13 stor134 smartd[2679]: Device: /dev/ada4, 104 Currently unreadable (pending) sectors (changed +64)
Mar 24 19:48:13 stor134 smartd[2679]: Device: /dev/ada4, 352 Currently unreadable (pending) sectors (changed +248)
Mar 24 20:18:13 stor134 smartd[2679]: Device: /dev/ada4, 2984 Currently unreadable (pending) sectors (changed +2632)

i am running smartctl -t long /dev/ada4
how is it possible such errors on a new disk array (raidz2) with a freenas running since few days?
have i to worry?

 

[Ericloewe]

how is it possible such errors on a new disk array (raidz2) with a freenas running since few days?

Hard drives don't care, they just fail.

have i to worry?

Yes, obviously. You need to replace that disk.

 

[danb35]

Bad sectors are always a bad thing. Rapidly-increasing counts of bad sectors are a very bad thing. That disk is dead, or at least mostly dead. Did you test it (and the other disk in your pool) before you created your pool?

 

[massmux]

yes i've checked before, but as Eric said, they dont care so much. In any case the mentioned disk has failed as expected and i succedeed in replacing.

i have another one in which there are about 100 unreadable sectors, that i hope will last until i can change this disk too

 

[danb35]

yes i've checked before, but as Eric said, they don't care so much.

Certainly a disk can fail at any time, but it's pretty unusual for a new disk that's gone through any sort of decent burn-in and testing (minimally, SMART test, badblocks, another SMART test). And for two of them to be going out at the same time under those circumstances is highly unusual--the only time I've seen something like that is when I bought a batch of "white label" hard drives.

 

[massmux]

yes you're right. infact i am quite upset. this was a purchase of 20 toshiba

 

[massmux]

even if i read in this link: https://dekoder.wordpress.com/2014/10/08/fixing-freenas-currently-unreadable-pending-sectors-error/

that other people having some problem, fixed with a zero filling the disk the unreadable sectors. but i did not tryied

 

[danb35]

Yes, some people have had success with that technique when there's a small number of unreadable sectors, even if I don't trust it myself. But you don't have "a small number of unreadable sectors".

 

[massmux]

yes let's say below 200 and not increasing

 

[joeschmuck]

My opinion would be to take all of those drives you purchased and run badblocks on them. Burn them in properly. A SMART Long test is a read only test, it's not good enough.