I have a FAS2240 and used it as an NFSv4 storage for our Linux
KVM-based cloud. Few days ago, I noticed a few NFS mounts freezing
up. After some investigation, looks like the Linux clients are
attempting to get access to files via NFS share and the Netapp appears
to be denying it. It appears to happen at random across multiple
clients as if we hit some kind of a wall.
I found a "lock status -v" command by going to some posts on the
internet and after running it, the last line shows the following:
Free owners 7; In-Use Owners 8185
Could that be the wall/limitation that's causing my problem? I also
learned of a bug in older Linux kernel that creates extra owners and
found the client that appeared to have a huge amount of file locks and
owners generated. After disconnecting the client and clearing the
locks it didn't seem to make a difference.
Here is some extra summary from the "lock status -n" command: