Lately i’ve run into a strange issue where an ESXi server gets into a state where VMs running on it are not able to be migrated to other ESXi servers. This is the error that comes up when you try to vMotion the problematic VMs.
A general system error occured: Virtual machine must be running in order to be migrated.
I’ve contacted VMware support and they tell me there’s no other way to fix this than to shutdown and powerup the VMs. Simply rebooting them does not work as the problem seems to be linked to their registration with ESXi or vCenter Server. You won’t be able to unregister them directly through tech support mode on ESXi either as it simply won’t let you while the VM is running.
After you do this, you had best reboot the ESXi server as well.
If anyone has come up with any alternate solutions, i’d love to hear from you.