VMware HA cluster`s node gives error

[Azamat]

Hi, everybody
i`ve some troubles with ESX HA cluster, which runnig on my 2x BL460c g5.
Periodically VMware HA cluster`s nodes give error - "HA agent on node in cluster HAcluster0 in CO has an error: Time-out while communicateing with the HA agent" and "HA agent on node in cluster HAcluster0 in CO has an error: Unknown HA error. and it doesn`t automatically repair, only "Reconfigure for VMware HA" action resolving this problem

thank you a lot!!!

[Nuwan Alwis]

Hi,
How did this happen suddenly? did you do any changes on your network?
HA cluster is highly dependent on DNS. So check if the both ESX can resolve vCenter and check it form the VC aswell.
seems like a network related issue
Could be switch configs or faulty NICs

[Azamat]

Hi,
Sorry, forgot to write that we have VMware 4 update 1
Network is fine, DNS resolves, ping shows that we don`t loose packages.
And also, the problems started after Update Manager did some updates and changed build version.