Easy Backup and Restore
Until recently the extent of my backup efforts was to take the occasional CD copy of my home directory and keep copies of important files somewhere else, usually on another disk partition or a floppy disk. All of this changed with the need to run some Windows legacy applications. The only machine really suitable for this work was my main workstation, a 1.2GHz Athlon machine, multibooted with four distributions. I decided to free up the first primary partition, which held Mandrake 9.0, and set up a Windows partition.
I freed up the first primary partition by transferring its contents to the seventh partition, overwriting an expendable Vector Linux 3.0 Distribution. To be totally safe, I booted into Debian 3.0 and mounted both partitions to individual mount points in /mnt. Then, as root, I used tar and a pipe to copy everything, including all links and permissions, from the source partition to the target partition. A few minutes later, after changing my GRUB boot menu, I was able to boot into Mandrake 9.0 Linux in the seventh partition and verify that everything worked as expected.
At this point, one normally would DOS-format the now free first partition and install Windows. I began to feel a little uneasy, however. Windows could format the whole darn drive or some other similar screwup could happen, in which case I would be in the position of having to fdisk the partitions and reinstall everything from scratch. The original disks, of course, would have all the applications except for those extra packages installed by me, but all custom configurations would be lost.
The machine now was running Mandrake 9.0, Debian 3.0 and Slackware 8.1. Of these, only losing my Slackware install would cause me grief, as it has been running like a top, boots to KDE 3.0 in less than 30 seconds--including my sign on--and is absolutely rock-solid stable. It also has the CUPS printing system set up perfectly for all of my printers on the LAN. So I must retain this setup at all costs. The solution, of course, is to back up fully everything from the Slackware install.
At this point, the desire to have a simple, easy and foolproof backup and recovery method took hold.
If you are a home or SOHO Linux user, I suggest that your backup and recovery system should:
Require no equipment or software other than what you already have
Be cost effective in backup media
Be easy to use regularly, or it will not be used at all
Be easy to verify, or it may be useless when the time comes
Require only the media and a working machine, in the hardware sense
Require only minimal knowledge of the recovery process when the crunch comes
A quick review of past Linux Gazette articles and a search of the Web turn up hundreds of backup solutions. Many are aimed specifically at the backup function; others are aimed at the repair and system recovery part of the overall effort to get back to some predefined state. Virtually none are customized for your system or your specific requirements, so why not roll your own solution? That is what we do here.
Most home or SOHO users do not have a tape drive system and are unlikely to purchase one for the sole purpose of backup, given that the cost of the tape system and software probably exceeds that of the computer itself. This essentially narrows our options to backup to removable disk, backup to the same or another hard drive, backup to a CD or backup over a network to some other hard drive. This last option essentially is a more complicated backup to local hard drive option, except there is zero chance of it being lost when your system goes down. So let us look at these options:
Floppy: Good for incremental backups on a daily basis and perhaps the best solution for saving work as it progresses, but useless for system-wide restoration. The LS120 Disk and the Zip disk are not large enough or common enough to be considered for the sort of simple but complete backup considered here.
Hard Drive: One can back up to a separate partition on the same drive, which is of little use if that drive fails, or one can back up to another hard drive in the same computer. This is good, except there is a fair chance that a power supply failure or nearby lightning strike could fry both drives--or somebody could steal the computer--leaving nothing to restore.
Network Filesystem Transfer: This is a good solution to back up and restore files for someone interested enough to correctly install it. however, it does nothing for the process of getting the system up again to the point where one can restore the files. In short, it's too complicated for most people to institute.
CD-ROM: This is where things begin to look interesting. These days most Linux users have a CD burner, and the availability of cheap CD-RW disks means the cost of maintaining something akin to the traditional rotating backup system is definitely manageable. This is the one for us.