TLDR; got a Disk Error on Disk 5, sort of fixed it by jiggling some SATA cables, some error during a parity check, but everything seems okay now,  I'm not sure if Disk 5 is healthy.

 

I recently re-racked my Unraid server, and immediately afterward, I received a Disk Error notification stating that 'Data on Disk 5 is emulated.' I read a couple of forum posts that suggested checking the SATA cables to ensure the connections were secure. This made sense since there was a lot of movement involved in re-racking the server. I turned the system off, reseated the cables, and then turned the server back on, and the error disappeared. However, when I ran the parity check again to make sure, I encountered a read error on Disk 5. Nonetheless, the parity check was confirmed successfully, and the data on Disk 5 is no longer emulated. I'm wondering if Disk 5 is actually failing or if I'm missing something here.

I would greatly appreciate any help in clearing this up for me and showing what to look for, for the future reference.

Many thanks in advance.

Disk 5 Extended Smart.zip full-diagnostics.zip

If it said the disk was emulated then it must have been disabled and showing a red X. But you don't mention that.

 

There are only 2 ways to get a disabled disk enabled again and no longer emulated. You have to rebuild the disk, or you have to New Config to reset the disk assignments and rebuild parity (by default).

 

But you don't mention that either. Instead you say you did a parity check. Something missing in your explanation.

 

# 1  Extended offline    Completed: read failure       10%     25703         96224840

Disk 5 has failed. You should replace it.

Hey @trurl

Thanks for looking into this. You're spot on about disk 5 – it went red and got disabled when emulated. After I fiddled with the cables and rebooted the machine, there seemed to be a sync error that Unraid sorted out. I figured it might be normal since I had a program writing to parity while disk 5 was emulated, and I only caught it later.

I'm gonna swap out disk 5 real soon to keep things running smoothly. Appreciate your help!

Question, why is disk 5 no longer emulated if there are unreadable sectors?

 

Something strange going on as once a disk is shown as emulated it should not leave this state until you have rebuilt it or taken some other action to force it to no longer be emulated.