Server not visible after installing VirtualBox and restarting

Question

As title. The server was working fine, I could ping it from the outside world, ssh in, it was serving up pages. I installed VirtualBox one day, and after a restart, I couldn't see it at all. The only way to access it was locally. All the of the networking configuration appears to be the same from what I can see, but I can't access it remotely at all. Another box on the same local network (the server has two network cards, one for internal network one for external) can ping the external as well as internal IP's no problem. I'm kind of at a loss here, I've tried everything I can think of, so this is my last resort before I just reformat.

It might be useful to know that I made a couple of virtual machines between installing VirtualBox and restarting. I also have tried removing VirtualBox.

The server is running Debian.

Answer 1

When you checked the configuration, did you notice if your NIC changed name? For example, is it now called eth1 instead of eth0?

I've seen this happen in hypervisor environment.

I'm no expert in linux udev stuff but I believe it has to do with the udev rules found in /lib/udev/rules.d/

For example, moving a Ubuntu machine from one Hypervisor to another might trigger a change in MAC address and therefore, it will change the NIC to eth1.

If you move that server again, it will change the NIC to eth2...so on and so forth.