I've got ubuntu 12.04 running as a virtualserver on virtualbox.
Last night there was a power surge and this morning I can't boot my virtual server.
I get a long error message. I picked this up:
VFS: cannot open root device "mapper/ubuntu--server-root" or unknown-block(0,0): error -6
when I do:
ls /dev/mapper
I get> control ubuntu--server-root ubuntu--server-swap_1
I can mount manually by doing
'mkdir /foo;mount /dev/mapper/ubuntu--server-root /foo'
I don't know what to do but I installed a tool and extracted this log http://paste.ubuntu.com/7119904/