I’m using Oracle’s VirtualBox 7.0.16 which currently has… issues:
ATTENTION: PLEASE REFRAIN FROM UPGRADING TO 7.0.16 FOR NOW. THIS RELEASE HAS AN ISSUE WHICH MIGHT CAUSE HOST OS CRASH WHEN VM IS CONFIGURED TO USE BRIDGED OR HOST-ONLY NETWORKING. WE WILL SEND AN ANNOUNCEMENT TO MAILING LISTS WHEN FIX WILL BE AVAILABLE FOR DOWNLOAD.
I only discovered this after a few BSODs on the host. One of my VMs is an Ubuntu Xenial that after such consecutive mistreatment kept getting stuck on Emergency Mode (EM).
At the beginning the log kept showing avahi errors, but after disconnecting NIC cables and even disconnecting the NICs and then gradually connecting them fixed that. Still stuck in EM.
Now it shows no errors, but it won’t boot either, always falls back to EM. My /etc/fstab is ok, i didn’t change the partitions.
Setting the default boot to graphical didn’t help either (it was the default anyway).
I did find it peculiar that the VM booted to a typical boot menu and waited for x seconds but paid no mind. (It used to just go straight to the boot option.)
Since there were a lot of answers out there pointing to fs corruption i ran fsck on the / fs without issue; but when i tried to run it on /home it wouldn’t ‘cos it’s an XFS fs. When trying the xfs tool if failed to load the appropriate module.
Then i noticed it was trying the modules of kernel x.y.z (the most recent) when the xfs modules are all in the other kernel x.y.y (the other boot entry).
After booting into x.y.y it booted fine. (Well sorta it won’t scale the screen but that’s another issue).