We have three 2012R2 Host Servers in a Failover Cluster, there are 14 Hyper-V VM’s in the cluster.
Yesterday Host3 went down because 3 network adapters disappeared. That left 2 servers (Host1 and Host2) active (that’s sufficient to run all the virtual servers). But for some reason all the virtual servers automatically moved to only one host server. One server cannot support all the virtual servers. However this server tried to run all the virtual servers which made none of the servers active. It showed all the vm servers “starting” but never “running”. By rebooting the host server that held the VM’s, all the VM’s automatically moved to the other good host server and the same thing happened.
So here are the 2 problems that happened:
- On Host3 three network adapters disappeared. And could not be recovered without re-installing the operating system. These are needed for the VM’s to run. The adapters are created when virtual switches are created in Hyper-V. The 3 are vEthernet (LAN Virtual Switch), vEhternet (iSCSI2 Virtual Network), and vEthernet (iSCSI 2 Virtual Network)
2. There does not seem to be any way of turning off a VM when it is in the “Starting” state.