HA problem with Virtualcenter 2.5 Update 2

As soon as Update 2 of Virtualcenter 2.5 hits the streets we started getting calls into support lines here at VMware about HA breaking.

Common reports include:

“insufficient resources to satisfy HA failover level on cluster” and “unable to contact a primary HA agent in cluster”

We think we know what is causing this, so I’m sharing this here in hopes of saving you a call.

The key is that all of your hostnames are in lower case only.

So, in Virtualcenter check-
-each host in the cluster, go to the configuration tab, DNS and routing, hostname
-everything needs to be lowercase
On each one of your ESX hosts-
ssh into each host and check-
-lower case names only in /etc/hosts
lowercase names only in /etc/sysconfig/network
cat /proc/sys/kernel/hostname

if not correct :

hostname <FQDN>

after this you can check the settings are correct using-

uname -n
hostname -a
hostname -s
hostname -d
hostname -f

in addition to this also make sure hostname in /etc/vmware/esx.conf is lowercase-

/adv/Misc/HostName = <FQDN in lowercase>
when done enable HA on cluster again.

Check this link if you are seeing the HA incompatible network message.