ESXi host disconnects from cluster

[tacticsbaby]

We are having a weird issue. After our database server was rebooted without notice one of our esxi 4.1 clusters has been having a host disconnect. I have repeatedly tried to reconnect this host and after a few minutes it disconnects again. I have tried disabling HA and reconnecting, but the host still disconnects. What should I do to resolve this issue as cleanly as possible? Thanks in advance.

[a_p_]

I'd suggest you take a look at the vpxa (ESXi host) and vpxd (vCenter Server) logfiles, to see whether they contain an information about the disconnect. Usually the issue you describe is caused by DNS resolution issue. Although this is most likely not the cause, please double check the ESXi host can resolve the names of the other hosts as well as vCenter Server.

For logfile locations, see http://kb.vmware.com/kb/1021806

André

[tacticsbaby]

Thanks Andre! I will check this out now. By the way to you and everyone else who participates in these forums Thanks! You guys are great!

[Troy_Clavell]

one other thing to check.  It could be the host record in your VCDB is corrupted.  An easy fix would be to remove the host from vCenter and add it back in.  This will not only reinstall the vpx agent but also add a clean record to your VCDB.

[tacticsbaby]

The problem is that I have a number of critical VMs on that host that are still running. Will this affect them?

[Troy_Clavell]

tacticsbaby wrote:

The problem is that I have a number of critical VMs on that host that are still running. Will this affect them?

no.  We've run into corrupted records a few times.  Disconnect and remove.  This will allow for the guests to continue to run with no impact.  When removed, add host back

[tacticsbaby]

Ok, before I do this I just want to verify that my VMs will keep running. I got a message saying that removing the host will remove all resource pools and VMs. Disregard?

[Troy_Clavell]

the VM's will continue to run and not be impacted.

[tacticsbaby]

Thanks Troy, the host was re-added to the cluster but it disconnected again.

[Troy_Clavell]

only one host and it started disconnecting after you DB server was rebooted?  If it were my environment I would also try a couple more things.  First being restart your vCenter Server Service and restart the management agents on the ESXi Host in question.

http://kb.vmware.com/kb/1003490

[tacticsbaby]

Thanks for all the help guys! It turns out this was the result of a number of things that came together when the virtual center database was rebooted. We had a "temporary" setting in virtual center that we used to point dmz hosts to virtual center. Guess it was forgotten about. When the DB went down it resulted in virtual center not being able to communicate properly with the hosts. Problem solved! Thanks again.