No network connectivity for a Azure VM

Question

Hi,

I would appreciate any thought on this one, I’ll continue to try and resolve but some additional guidance might get me there faster.

A couple of months ago we used our backup software to create some offline virtual machines in order to work towards migrating them. They got put into a different subnet on an existing Vnet so they couldn’t talk to anything live like domain controllers etc whilst testing was completed.

We agreed they were good working replica’s and over the weekend I shut the physical boxes down and moved the Azure boxes onto the live subnet. One of the machines needed its computer account reseting in the domain, which is fine and is now back on the network without issue.

The other machine I lost contact with, it showed as running with an image present showing CRTL ALT DELETE screen but not possible to connect to it. I’ve removed cards, added cards, moved it back to the subnet, different public addresses, nothing.

I wondered if somehow the firewall had re-armed itself hence the lack of traffic. So to check this and turn it off I took a snapshot of the disk, converted it to a real disk and booted it in a Hyper-v environment. Firewall wasn’t on, nothing very interesting in the event log.

Before I shut it down, I enabled the serial console as its an old 2008 R2 box without that capability built in.

Loading back up in Azure, I can get to it via the serial console now and the Azure nics don’t appear to be present in the system only a one with the same MAC address as it had in the physical world.

Any suggestions to make it see the Azure NIC’s? I’ve already done the redeploy things that Azure suggests.

Thanks in advance.

Lee

Answer 1

Hi Lee Read,
Good catch! Glad the issue is resolved for you finally. I will have this answer promoted by reposting it. As the Original Poster, you will not be able to accept your own answer. As you mentioned, if anyone faces the same issue, this attempt to help others by providing a solution can be very beneficial. If accepted and marked as verified, this solution will be highlighted, making it easier for others to find the verified answer quickly.
Thanks again for sharing the solution here. Have a good day!

Issue:
No network connectivity for an Azure VM
Solution:
For some reason PnP got itself so screwed up that it refused to install any new hardware it saw, so when the machine was on the Azure network, no cards we being installed so no traffic.

Booted the OS disk in Hyper-V and cleared some motherboard devices like PnP and PCI components in an attempt to force the system to re-check hardware. That worked and the NIC’s I’d installed in Hyper-V appeared.

Loaded it back into Azure and it attached straight to the network.

Lee