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Cringely's P2P Backup Idea
gewg_ writes "If Napster and Bit Torrent had a baby, would it Baxter?
As a follow-on to Cringely's
last column where he talked about having a backup strategy in the
wake of Hurricane Frances, this week he proposes a distributed RAID notion as a solution."
Baxter is, of course, the famous IRC client for BeOS. (Hi, Seth!)
Get off my launchpad!
In case they missed it.
"Backups are for wimps. Real men upload their data to an FTP site and have everyone else mirror it."
Cringley's not the first with this kind of idea. In fact, the Freenet Project already implements something to this effect. Although not specifically designed for reliable backups, the distributed caching algorithms essentially replicate data towards where it's most often needed, helping to improve network performance and creating copies of important data along the way so that it won't be destroyed if a central server fails. Obviously not a commercial solution, but very interesting.
I just went through Hurricane Ivan in Grenada. If you have been watching the coverage you should know that our island was completely destroyed. There is no water, no electricity, and no security. The university I attend (St. George's) lied to the students' parents about our situation. There were looters with guns and machetes threatening students. The first two nights we fended for ourselves with a large bonfire and homemade weapons, knives, pipes, etc. The third night we had 10 minutes to pack up and leave since we could see the looters lighting fires to apartment buildings on the road we were on. I quickly took the hard drives out of my two laptops (and the external drive I have), picked up a GSM roaming phone, any cash I had, a passport and two pairs of clothes. We ran to campus. Campus had about 200 male students lighting bonfires and running security teams to monitor the area. We chartered our own jet out of Grenada yesterday to Barbados which is where I am writing this from. My point is this: no one cares about data in this situation. No one wants to know about RAID or tape backups. If it came down to it, I would have ran with only a passport, a phone, and cash. We were worried for our lives and whether we had water or not, data was not our concern. People need a reality check. How many of you can claim that you went through a Category III or IV hurricane on an isolated island fending for their lives? Not many, so quite franly Cringely can go to hell.
This idea is poorly thought out. It has a couple of *major* flaws, imo.
#1) It doesn't recognize the reality of the complexity of backup software. Kinda easy to gloss over 'automated' backups without ever describing it. Pretty hard to imagine some piece of software that can universally back stuff up on everyone's hard drive and at the same time be very easy to use. Imagine mom/dad trying to use software with similar capabilities to Veritas BackupExec isn't easy. And.. imagine the wide variety of live files and databases that it wouid have to handle.
#2) Data integrity. He suggests a 1:1 ratio for backup space. Not hardly. How is he going to have any kind of redundancy with that? Crashes and people unsubscribing will happen all the time. The data would have to have a *lot* of tolerance to that.
A parity solution wouldn't be nearly enough. That assumes that only 1 failure at a time happens (using RAID 5 as my basis here). It would be easy to imagine that one person unsubscribed with part of your data and another had a crash or corruption problem.
So.. complete mirroring would be necessary. Again, its easy to imagine 2 people's system going offline at the same time.. so, you'd probably need more than 2x Mirror. At this point... how much is enough to ensure reliability? 3x 4x 5x ? ? ? How much do you trust your average netizen?
So.. pick your number and then divide your backup space by it. Like 5x? Add 10GB and you have 2GB usable storage. Not very good.
I'll just skip over the 'auto backup' of people's 40GB storage over a 128K up line for now.. already typed too much...