It's made the news yesterday, but in case you missed it, there seems to be a bug within vSphere 5.5U1 that affects all NFS users.
NetApp & VMware (at least, maybe Nutanix too?) are working on the subject.
See the post below for more information:
That may also explain the delay from Nutanix in the support of the 5.5U1?
Did you guys catch this while working no the 5.5U1 support?
The ESXi 5.5 U1 NFS datastore disconnect issue has occurred both internally and with our customers. Field advisory #17 was sent to our customers yesterday advising them to postpone any upgrades to ESXi 5.5. U1.
Looks like vmware just posted KB-2076392 on this issue.
Frequent NFS APDs after upgrading ESXi to 5.5 U1 (2076392)
When running ESXi 5.5 Update 1, the ESXi host frequently loses connectivity to NFS storage and APDs to NFS volumes are observed. You experience these symptoms:
Thanks, very clear.
Too bad, we were to test the 5.5U1 just next week to rollout massively starting next month, guess we'll have to wait...
Sure you know already but in case anyone see's this thread and isn't aware, a patch to 5.5U1 was released by VMware this week. Nutanix are internally testing it I believe. We await the results eagerly