If you don't want to take any chances with your data, it is recommended that you backup hard disk partition table. Last Friday I was discussing some issues with one of our customer and he pointed out me dd command.
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=/tmp/sda-mbr.bin of=/dev/sdX bs=1 count=64 skip=446 seek=446
dd command works with Solaris, HP-UX and all other UNIX like operating systems. Read man page of dd for more info.