One cluster is having this issue
This cluster consists of 3 ESXI hosts supporting 2 Virtual servers (2012 r2).
One server still has perfect connectivity. They are both on the same distributed vswitch. The one that 'dropped' off the network over the weekend cannot be re-added to the network, as it cannot reach the default gateway or DNS servers - the settings match the one that works (default, subnet, DNS servers).
I have deleted the network card and re-added, but that didn't help. I did get the link to go from white (down) to green (up) when looking at that distributed vswitch. It even shows the MAC address now. The machine still won't ping out (or let anything ping it). I know the domain name is fine, as it resolves to the correct IP address.
Edit: Also ensured remote access is enabled.
This doesn't sound like it could be anything other than an issue inside the Windows Server guest. Has it been rebooted?
Do we have NSX ? Is the gateway on Egde?
Can you try migrating the non working VM to the host where the working VM located and then check the connectivity ? This will help you to isolate if the issue is at Guest OS or physical networking.