Recently we had an issue where one of our servers unexpectedly crashed and we had to hard reboot it. When it rebooted we began seeing kernel panics and it would not complete its boot cycle. In comes my mfsbsd stick to the rescue! The machine in question was running FreeBSD 10. We had just built it so we had one of these sticks handy. To create a mfsbsd stick yourself grab the image here:
http://mfsbsd.vx.sk
FreeBSD Build Image Instructions:
http://www.freebsd.org/doc/en/articles/remote-install/preparation.html
We ended up using Win32 Disk Imager:
https://sourceforge.net/projects/win32diskimager/
Once we got booted off the usb stick to a command prompt (beyond the scope of this post but simple, follow the prompts) we simply did the following to remount the zfs pools that were fubar’d:
zpool import -f -a
All zfs pools imported with no problems. Then we rebooted the machine as normal and voila, no errors!
My-IT.log by Steve Dickinson 