I have a couple of virt-manager virtual machines for doing DHCP-related work. I have one for the DHCP server and one for the DHCP client, and I have a private network between the two so I can simulate DHCP requests without messing up anything else. It works nicely.
I got a bit carried away, and I use LVM to snapshots for the work I do, so that when I'm done I can throw away the virtual machine's disks and work with a new snapshot next time I want to do something.
I have a cron job, that on a good day, fires up the virtual machines using the master logical volumes and does a dist-upgrade on a weekly basis. It seems to have varying degrees of success though.
So I fired up my VMs to do some investigation of the problem for #749410 and discovered that they weren't booting, because the initramfs couldn't find the root filesystem.
Upon investigation, the problem seemed to be that the logical volumes weren't getting activated. I didn't get to the bottom of why, but a manual activation of the logical volumes allowed the instances to continue booting successfully, and after doing manual dist-upgrades and kernel upgrades, they booted cleanly again. I'm not sure if I got hit by a passing bug in unstable, or what the problem was. I did burn about 2.5 hours just fixing everything up though.
Then I realised that there'd been more activity on the bug since I'd last read it while I was on vacation, and half the investigation I needed to do wasn't necessary any more. Lesson learned.
I haven't got to the bottom of the bug yet, but I had a fun day anyway.