Reallocated Sector Count = 352 on new drive

[Geck0]

Hi,

My latest disk, which is disk 5 Ironwolf Pro ST16000NE000 has a Reallocated Sector Count today of 352. This drive is my newest addition.

One of my cache pools, single SSD Ironwolf Pro failed yesterday and had to be removed. I took it out of the pool but didn't disconnect it and it was still causing the log to fill up.

This resulted in not being able to shutdown the server properly and I eventually had to a hard shut-down.

I'm now seeing this, which may not be be related but all my other drives are Reallocated Sector Count = 0.

 

To me, it seems quite a high number for a new drive. I'll do an extended smart test in a sec. But I wanted to get some advice on whether I should move the data off there and run an extended pre-clear or keep going in the mean time until I receive a new drive and let parity rebuild it?

I don't want to face data corruption, so whatever is best and safest to do.

 

Currently, there is very little on the drive. The only other thing I can think of is if I managed to knock a cable when removing the failed SSD, which I doubt, its a spacious case. The drives are connected to an LSI controller.

 

I've attached the diagnostics. Any help is always appreciated, I probably need to do a bit of reading on what to look out for on these SMART reports.

nexus-diagnostics-20230516-1817.zip

[JorgeB]

If it passes the extended SMART test keep until the new one arrives.

[itimpi]

2 hours ago, Geck0 said:

To me, it seems quite a high number for a new drive. I'll do an extended smart test in a sec. 

I agree - anything other than 0 on a new drive is a cause for concern.   Possible the drive got damaged in transit.

 

2 hours ago, Geck0 said:

The only other thing I can think of is if I managed to knock a cable when removing the failed SSD

That should not cause reallocated sectors as they happen completely internally to the drive.   I guess it might be possible for a power cabling issue to cause this but I would be very surprised if that was actually the cause.

[Geck0]

@JorgeB Thanks for your input. I'm going to keep it running. I've ordered a new 20TB, but it will take a couple of weeks to get here.

@itimpi I agree with your comments. Cabling was the only issue I could think of.

 

I'll use it as normal and keep an eye on the reallocation count. I don't know if its neccesary to exclude the drive from Share folders in the meantime??

I'm guessing a new drive virtually empty, with no increase in reallocation has a relatively low risk, as there is space for further reallocation.

 

For those that follow, I hadn't seen this on the Unraid wiki page;

Understanding Smart Reports

[Michael_P]

39 minutes ago, Geck0 said:

I don't know if its neccesary to exclude the drive from Share folders in the meantime??

I'm guessing a new drive virtually empty, with no increase in reallocation has a relatively low risk, as there is space for further reallocation.

 

Depends on your tolerance for risk - if another drive happens to fail you'll need it and the rest to stay healthy enough to rebuild 

[Geck0]

@Michael_P My tolerance is low. I wasn't referring to removing the drive, but excluding it from Share folders to stop any further writes to it. I haven't got much of a choice at the moment, I have to wait a couple of weeks for a new drive to show up. 

The one that's causing me aggravation was actually a brand new, redundent drive which I had in my case for a couple of months, ready to go in case there was an issue like this or low disk space. 

I ended up allocating it to the array recently and probably should have ordered another one at the same time, now its a 2 week wait for a new cache drive and a replacement drive for the array to show up.

 

[Michael_P]

6 minutes ago, Geck0 said:

but excluding it from Share folders to stop any further writes to it

 

It's the bashing it'll take if you have to rebuild any other drive in the array that would be the killer. My experience with Seagate drives hasn't been good, they typically keel over rather quickly once they start failing. If you don't have your "can't lose" data backed up, now's a good time