KerbyServer

On multiple occasions I have had to modify a broken file on a Fedora system that was preventing me from booting. More recently this has been the /etc/fstab file. If any lines in that file have issues, Fedora will stop booting and throw you into a recovery console. Unfortunately, that console has the root partition mounted read only, so good luck fixing that file :)

To remedy this, I have been using the Ubuntu Live CD. The issue with this approach, though, is that the Ubuntu install on the CD does not have support for the LVM logical volumes that Fedora sets up as a standard part of its install. Here are the steps to utilize the Ubuntu Live CD to modify files on a Fedora LVM logical volume:

1. Boot the system from the Ubuntu Live CD.
2. Open a terminal and install LVM support with: sudo apt-get install lvm2
3. Then run the following commands:
   sudo modprobe dm-mod
sudo vgchange -ay
mkdir -p /mnt/VolGroup00/LogVol00
mount /dev/VolGroup00/LogVol00 /mnt/VolGroup00/LogVol00

4. At that point, the logical volume can be accessed in the /mnt/VolGroup00/LogVol00 directory...so make any file changes and reboot!