I'm testing upgrade paths to vSphere from ESX 3.5 update 4 on a IBM BladeCenter with 2 hs21 xm blade servers; i'm going through several problems and the last one is the one mentioned in the subject of this thread.
In this scenario i upgraded vCenter succesfully then i took all VMs on a single esx 3.5 host, i removed the other host from the cluster and then from vCenter, then i made a fresh install of vSphere, i reconnected the host to the cluster then i did the whole procedure again with the second node. At the end i have two hosts with vSphere installed but i had to disable HA in my cluster since i always get this error when i try to configure HA agents on the hosts, but i have to say that DRS works ok.
In the release notes of vSphere, in the known issues section i can read:
"Upgrading from an ESX/ESXi 3.x host to an ESX/ESXi 4.0 host results in a successful upgrade, but VMware HA reconfiguration might fail
When you use vCenter Update Manager 4.0 to upgrade an ESX/ESXi 3.x host to ESX/ESXi 4.0, if the host is part of an HA or DRS cluster, the upgrade succeeds and the host is reconnected to vCenter Server, but HA reconfiguration might fail. The following error message displays on the host Summary tab: HA agent has an error : cmd addnode failed for primary node: Internal AAM Error - agent could not start. : Unknown HA error .
Workaround: Manually reconfigure HA by right-clicking the host and selecting Reconfigure for VMware HA."
The problem is that this workaround doesn't work for me, so i was wondering if someone, once again is able to help me with this issue.
Thanks in advance for your support.