So if you run ESXi 4 and upgrade vCenter to Update 1, you run the risk of experiencing the vCenter agent bug. IF you run your vCenter server as a virtual, you are using vNDS, and you lose connectivity to a host and that host happens to be running the vCenter VM...you are in for an interesting day since you will lose the ability to manage the vNIC assignments and the host once reconnected to the cluster (after running the patch install, which means you have to at least pause all the VMs on that box) will not see the original vNDS port groups. Its a mess!!!
I strongly suggest no one who is running vNDS run their vCenter server as a VM. Who knows when something like this bug might happen again and it cost me all of last weekend to get my stuff back in a manageable state.
- Steve
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Steve Brill
Virtualization Junkie
VMware, SAN/NAS, Networking and Server Infrastructure Engineer
