While setting up a lab using Hyper V. A couple of little bugs have been found
You set up an External Switch and share your NIC with the OS.
– You find you network connectivity dies.
To fix, go to your Network Connections. Find vEthernet (Your Switch Name). Disable and Enable. Your network connectivity should restore.
You set up Internal Network (Host and Guest only).
You configure vEthernet (Your internal switch name) with an IP in the same subnet as your guests. The guests are configured to connect to this virtual switch.
– There is no connectivity. i.e. You can’t RDP to your Guests, No admin share from Guest to Host etc.
To fix, same as above. Disable and Enable the virtual NIC. Connectivity between your Host and Guests should restore.
Unfortunately, it appears you need to do this each time you boot your Host. I haven’t found a permanent fix yet.
Upgrade to Windows 8.1
This problem doesn’t exist in Windows 8.1. Upgrade and rid yourself of some pain.