Last week while working at a customer, we migrated their VM’s from a Standard Switch to a Distributed Switch using the “Migrate Virtual Machine Networking” wizard.
After the migration, some VM’s appeared to be connected to two Port Groups, even though they only had one Network adapter configured:
Even when looking at the hosts switch configuration, the VM’s did show up twice, once connected to the Standard Switch, and once to the Distributed Switch.
After some investigation I found a knowledge base article that told me how to fix this:
Symptoms
- After migrating virtual machines from a virtual switch to a virtual Distributed Switch (vDS), you see both old and new network entries for the virtual machine in vCenter Server.
- In vCenter Server, the VM settings have entries for both the old standard port group and the newer distributed port group.
- The virtual machine properties and the .vmx configuration file reference only the vDS configuration.
Cause
Resolution
To work around this issue and to remove the reference to the virtual switch network entry, delete the virtual machine snapshots.
In a way, this behavior kind of seems to make sense.
Say you migrate a VM that has a snapshot from a Standard Switch to a Distributed Switch, and you would revert to the snapshot, your VM would reconnect to the Standard Switch …
So the double connection kind of warns you there are other networks configured in previous snapshots.