chroot into an off-line Linux version using a LiveCD/USB
It's not just as simple as running the chroot command, you need to ensure the /proc and /dev entries are passed through and populated to the chroot environment.
Step 1 - Mount Your Off-line OS
mount /dev/sda1 /mnt
Step 2 - Mount Proc
mount -t proc none /mnt/proc
Step 3 - Mount Dev
Most guides will tell you to use this: mount -o bind /dev /mnt//dev but that doesn't work for some reason in many cases:
mount: wrong fs type, bad option, bad superblock on /dev,
missing codepage or other error
In some cases useful info is found in syslog - try
dmesg | tail or so
So the work around is to use the following (unless the above works for you, I believe maybe newer versions of mount will be fine):
cp -a /dev /mnt/dev-temp
mount --bind /mnt/dev-temp/ /mnt/dev
Chroot in!
Everything should be fine, I can see my disks and everything functions as normal. The bad part/side effect is the fact that for some reason I can't see my mdadm entries.