I have a Hyper-V 2012 R2 server with two VMs on it, both are running a virtualised 2008 R2 server. On the VM in question, it has lost network access three times and I get it back on the network by changing the vNIC to another one. Then a week later (always at night), that NIC looses connection so I put it on the same NIC that the server VM is on as that has no issues with network access.
I have removed the V NIC and added it again, but it did not make a difference.
I have Hyper-V Replica set up on both VMs (5mins) and Altaro backing up both VMs to an iSCSI NAS.
The NIC is a default setting with no VMQ and no SR I/O enabled.
Does anyone have any ideas?