07-24-2009 04:13 AM
We recently had a disk failure in our EVA4100.
This was the sequence of events:
A physical disk drive has been rendered inoperable.
A physical disk drive has disappeared.
A member management operation has started due to the appearance or disappearance of a physical disk drive.
At his point the disk has become 'unidentifiable'
The Diskgroup status changes to 'Leveling'
After 8 hours Leveling reaches 100%
But Leveling then starts all over again:
Leveling of capacity in a Disk Group has started.
There are a couple of things I'd like to ask:
1) Why does the EVA perform the second leveling phase?
2) At what point is it safe to replace the disk (not necessarily add it to the diskgroup, but just replace it)?
Solved! Go to Solution.
07-24-2009 06:00 AM
07-24-2009 06:50 AM
The EVA sometimes does, erm, undocumented things.
> 2) At what point is it safe to replace the disk
According to the "configuration best practices white paper" (4AA0-2787ENW) you should wait for the data reconstruction (= VRAID rebuild) to finish, before you start with removing the old disk. You have to check the controller event log to find out :-(
The data leveling starts after the reconstruct, but you don't have to wait for leveling to finish.
07-24-2009 06:58 AM
The weird thing is, the first Leveling took 8 hours, now the second one is at 2% after 3,5 hours.
We also have twice as high as normal iowaits on the servers with EVA Vdisks attached.
The leveling seems to take away IO performance, while not making any substantial progress itself.
Btw, our software version is SR1142xc3p-6200
07-24-2009 07:23 AM
indicate the start of the reconstruction?
If so, then that seems to have finished after 8 hours, indicated by events:
"A member management operation has finished"
"A Volume was removed from a LDAD"
"A Disk Group has transitioned to the NORMAL state"
I'm not sure why EVA started a leveling process right after that, when we haven't replaced or added the new disk to the diskgroup yet.
Thanks for the whitepaper link.
07-24-2009 08:32 AM