From http://www.cyberciti.biz/tips/linux-how-to-backup-hard-disk-partition-table-mbr.html :
"Backup MBR with dd command
dd the old good command which now backup partition tables even writes CDs ;). Backing up partition is nothing but actually backing up MBR (master boot record). The command is as follows for backing up MBR stored on /dev/sdX or /dev/hdX :
# dd if=/dev/sdX of=/tmp/sda-mbr.bin bs=512 count=1
Replace X with actual device name such as /dev/sda.
Now to restore partition table to disk, all you need to do is use dd command:
# dd if= sda-mbr.bin of=/dev/sdX bs=1 count=64 skip=446 seek=446"
