We have had some issues with our Linux guests, especially CentOS 5 and 6, on our VMware ESXi 4.1 cluster during times of vmotion events. For example, after a vmotion migration, our CentOS hosts appear to be powered on, but you cannot access them or interact with them inside of the console in VCenter. I was curious what the requirements are for the guest VM configuration in order to make this successful. Does one need to have VMware Tools installed for all of the Linux guests to allow vmotion to work? We have VMware tools installed on all of our Windows guests and none of our Linux guests right now.
SnapOverflow
You don't need to have the VMWare Tools installed in order to leverage vMotion. However, it makes sense to have the VMWare tools installed in your Linux guests for other management and performance reasons.
it's very easy to check - take a VM, install vmtools, and run a migration. If you can't reproduce the issue with tools installed, you've got it nailed. If not - look elsewhere (I'd start with vmware techsupport)
I know that with HyperV, in order to be able to successfully perform a live migration of a linux host we have to set the virtual nic to use a static MAC address. The usual for a windows guest is to have a dynamic MAC address assigned. It's possible that VMware has the same requirement.