NFS mounting and DNS behaviour

[GrumpyOldMen]

We were having a 10-node cluster and reduced it to 4 nodes. On the cluster we did have some svm's using NFS. Each SVM's did have 10 lifs, 1 lif per node. As we reduced the amount of nodes to 4 with did want to do a cleanup of the LIFS, so removing IP-addresses... We did it using following steps:

• Adapt DNS so only 4 instead of 10 IP-addresses will be used
• We waited for 14 days and then brought down the LIF's

What happend?

• A lot of servers were not able to mount the SVM's anymore but i don't understand why, as mounts are done using FQDN...

Any idea's.... Does the NFS-server remembers the IP-address when doing the mount initially or .... ?

[AlexDawson]

Couple of things that might cause it

- DNS lookup is done at mount time, not periodically. Meaning the clients would stay mounted to whatever IP address they got 15+ days ago.

- On remount/reboot, the NFS server hostname may be in /etc/hosts on the clients due to well meaning config scripts