[gpfsug-discuss] Bad disk but not failed in DSS-G

[Jonathan Buzzard]

On 20/06/2024 22:02, Fred Stock wrote:
> 
> I think you are seeing two different errors.  The backup is failing due 
> to a stale file handle error which usually means the file system was 
> unmounted while the file handle was open.  The write error on the 
> physical disk, may have contributed to the stale file handle but I doubt 
> that is the case.  As I understand a single IO error on a physical disk 
> in an ESS (DSS) system will not cause the disk to be considered bad.  
> This is likely why the system considers the disk to be ok.  I suggest 
> you track down the source of the stale file handle and correct that 
> issue to see if your backups will then again be successful.
> 

There is a *lot* more than a single IO error on the physical disk, the 
output of mmvdisk pdisk list for the disk shows

       IOErrors = 444
       IOTimeouts = 8958
       mediaErrors = 15

And the output of dmesg shows loads of errors. I have not attempted to 
count them but it is again a *lot* more than a single IO error. That 
disk should have been kicked out the file system and the fact that it 
has not is a bug IMHO. Anyone who thinks that is "normal" and not 
"failed" is as high as a kite.

Also mmbackup has now failed for three days in a row with different 
stale file handles building the change lists, making this is an on going 
issue.

So can I safely use the --force to get this dodgy disk out the file 
system? It is the *only* disk in the system showing IO errors so almost 
certainly the cause of the problems. Unless you are aware of some Linux 
kernel bug that causes otherwise healthy disks in an enclosure to start 
having problems. I guess there is an outside chance there could be an 
issue with the enclosure but really you start with the disk.


JAB.

-- 
Jonathan A. Buzzard                         Tel: +44141-5483420
HPC System Administrator, ARCHIE-WeSt.
University of Strathclyde, John Anderson Building, Glasgow. G4 0NG