Back up drive

Back up a linux system to a second bootable drive

Steps:

We want to copy all files from the root drive to a new drive.
We also want to update the boot menu to boot off the new drive.
We also want to change /etc/fstab on the second drive to use the new root path.

These are the steps for backup of the dune box to the /spiceflow/2.0tb-newmovies/ drive. When we're done, we'll boot from that drive to prove we have a working standby system.

rsync does an excellent job of copying just what we need. Test it with this:

# a (archive mode -rlptgoD) v (verbose) x (don't cross filesystems) h (human-readable) n (dry run)
rsync -avxhn --progress / /spiceflow/2.0tb-newmovies/

Do the job with this:

rsync -avxh / /spiceflow/2.0tb-newmovies/

  sent 28.10G bytes  received 8.64M bytes  15.63M bytes/sec
  total size is 39.57G  speedup is 1.41

There was def some old stuff in there worth cleaning up:

/home/m/development/svn/mythtv...
/var/tmp
xbmc log files
etc

Next we fix /etc/fstab on the new drive to use the drive as root. Original config:

/dev/disk/by-label/d-g2-root        /                           ext3    noatime         0 1
/dev/disk/by-label/d-sp-20newmovies /spiceflow/2.0tb-newmovies  ext4    noatime         0 2

New config (remember tho, we lose the 2gb drive):

/dev/disk/by-label/d-g2-root        /root-hot-drive ext3    noatime         0 1
/dev/disk/by-label/d-sp-20newmovies /               ext4    noatime         0 2

Note: this never worked out for me due to my system's mix of ext3 and ext4. I'll retry once I migrate everything to ext4. Next, grub:

mount /boot
em /boot/grub/menu.lst

Orig entry:

title                                ----- linux-2.6.34-gentoo-r11_withext4
root (hd0,0)
kernel /boot/linux-2.6.34-gentoo-r11_withext4 root=/dev/sda4

Add a new "standby" entry under it - do a "df" to find the root:

title                                ----- ==STANDBY== linux-2.6.34-gentoo-r11_withext4 
root (hd0,0)
kernel /boot/linux-2.6.34-gentoo-r11_withext4 root=/dev/hda1

Then reboot to standby and see what we have... (no "latest" video library etc., but otherwise the same?)