Moving a live system from one hard disk to another

Ever found yourself in the situation where you want to move your GNU/Linux from an old hard disk to a new one? Well, it can be done quite easily

First, set up new partitions with parted then mkswap, mkfs (using proper labels). Yes, I assume you’re familiar with these (RTFM).

Mount the new root partition somewhere, like /mnt/tmp in this article.

Create in this new partition all the directories that it would not make sense to copy from the original system (in my case: home being on another partition, stockage containing only NFS mounts):

cd /mnt/tmp
mkdir dev  home  proc  stockage  sys  tmp mnt

Shut down any daemon/service that is up (cron, etc), to avoid copying stuff in an incoherent state.

Then, actually copy the system:

for dir in /*; do if [ ! -e /mnt/tmp/$dir ]; then cp -ax $dir /mnt/tmp/; fi ; done

Edit /mnt/tmp/etc/fstab to use the newly created partitions.

Chroot in the new system to make it bootable with grub:

mount --bind /dev /mnt/tmp/dev
mount --bind /sys /mnt/tmp/sys
mount proc -t proc /mnt/tmp/proc
chroot /mnt/tmp
grub-mkdevicemap
update-grub
# (you can run blkid to check the root's unique id of this
# new system shows up in the new system /boot/grub/grub.cfg)
grub-install /dev/XX  # where XX is the new disk, like /dev/sdc or whatever

Reboot on the new system (stating the obvious: change boot drive order in the BIOS). If everything is fine, then copy /home from the old disk to the new partition, without login in with any system (CTRL-ALT-F2 to quite X server and log in as root, for example).

After removing the old device, re-run update-grub so it’ll no longer show up. The end.

Update: Please take a look also at the following backup script that clone a live system to a secondary hard drive.