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Editor's Note: The Motley Crew Collection of Backup Schemes and Devices

Apr 09, 2010, 23:04 (11 Talkback[s])
(Other stories by Carla Schroder)


Desktop-as-a-Service Designed for Any Cloud ? Nutanix Frame

by Carla Schroder
Managing Editor

Back in the olden days tape backups ruled. I never did like tape. It took too long, it was noisy, and restores were painfully slow. Most backup software was operating-system dependent, which made bare-metal restores pure pain. First reinstall the OS, then the backup software, and then if the gods were kind you could actually find and restore your data.

This modern era is much better, because we have all kinds of fast and inexpensive ways to make large backups, and even better, to make fast restores. I am all about simple and easy. So my favorite is using plain old rsync and hard disks. This is my standard rsync incantation:

rsync -av --delete  /home/carla/ /media/disk/backup/
I'm fairly diligent about keeping my files pruned of cruft, and browser caches and trash empty, so I just backup my whole home directory. -a means archive, or preserve everything as-is, such as permissions and ownership, and recurse into subdirectories. -v is verbose, and --delete means if I delete something from my computer, then it should also be deleted from the backup.

There are all kinds of ways to refine and pretty this up with scripts, and to exclude files and directories. rsync is efficient because after it copies a file the first time, it only copies changes on subsequent backups. So your backup drive needs to be larger than the drive you're copying, but not hugely larger.

Some folks prefer to compress their backups with good old tar. tar is reliable and easy to use, and you save a lot of space. But I prefer rsync because I can read my backup drive just as easily as the original, so when I want to restore files it's simple copying, and no fussing with unpacking archives.

Backup Hardware

The time is coming when I will have to break down and build a proper fileserver for my home network. But for now I use single SATA hard drives in USB enclosures, and USB sticks. (Like Rosewill's external USB enclosures, which cost under $20 and work just fine.) They're fast and easy, and I can plug them into any computer to read them. Well, any Linux computer, since Mac and Windows are so deficient in their filesystem support.

Long-term archiving is still a problem. SATA drives should outlast USB Flash media. But who knows how long they will last. USB sticks are nice for short-term project backups, and sneakernetting multi-gigabytes of audio and image files.

Really Important Stuff

Very important data go offsite to Spideroak.com. They have been reliable, have a lot of nice remote access and sharing features, and what I like best--"zero knowledge data encryption". They cannot see your data because you get a unique encryption key. If you forget your password, wave bye to your stuff. This is totally fine with me because I like to think of myself as a grownup, rather than the mythical dimwitted user targeted by operating system developers, who think we need to run multiple commands to really delete something, because deletion is scary and dangerous and maybe we don't really mean it.

I used to share offsite network backups with friends, some simple rsync transfers and encrypted directories. I'll do it again when I can find someone suitable to peer with.

Next week let's talk about what goes into a good reliable storage server. Hint: RAID 10, not RAID 5.