For the last few days while running a Windows 2012 R2 x64 server which was originally built on VMWare 5.1.x,, but moved to a 5.5.0, this servers network card appears to be dropping out and all network traffic stops altogether.
Restarting services wasn't good enough to start the network again, only a complete machine shutdown and restart worked. This made some of the interested parties quite irate. And me.
There were a number of thoughts that crossed my mind - recent firmware patch, physical network switches, SAN connectivity, VM (virtual) Hardware, Windows OS, Windows software. Each were ruled out until VM hardware was left.
Digging through the VM Properties, I'd spotted some settings that I'd disregarded before.
Guest Operating System and Network adapter type.
Guest OS was set to Windows 2008 R2 x64 as there seemed to be a bug in 5.1 for us where the Virtual machine wouldn't even start up to install the OS if W2012x64 was chosen at machine build, but downgrading to W2008R2x64 worked. Doing that however defaulted the network adapter to be E1000. The default Adapter for W2012x64 is E1000E.
At the next network halt several steps were made.
1. Removed the Server from the Inventory (***REMOVE NOT DELETE!!!!***)
2. Created the new VM and chose the OS to be W2012x64
3. Moved the virtual hard drive from the SAN to local storage (this machine was supposed to be running locally - not from the SAN).
4. Added the correct IP address back to Windows and unbound it from the network card that is no longer being shown in Windows.
5. Removed the old version of VMWare tools which the machine knew wrongly was Window2008R2x64 and installed the version for Windows 2012 instead
The machine seems more responsive while RDPed onto and has been stable for a good few hours now :/ Or maybe that's some hope from a System Manager
