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Why Do Companies Backup So Infrequently?
Orome1 writes "Businesses are on average backing up to tape once a month, with one alarming statistic showing 10 percent were only backing up to tape once per year, according to a survey by Vanson Bourne. Although cloud backup solutions are becoming more common, still the majority of companies will do their backups in-house. Sometimes they will have dedicated IT staff to run them, but usually it's done in-house because they have always done it like that, and they have confidence in their own security and safekeeping of data."
Seriously. Most people aren't willing to put in the effort to determine just how bad things would be if they had to resort to their (often inadequate) backups, and therefore they aren't willing to pay the time and capital to get adequate backups.
If you want your company to get better backups, run a simulation of what would happen if something failed. What's the best recovery you could do? What business would you lose? Then calculate the probability of that failure occurring, and be generous.
Insert self-referential sig here.
Disclosure: I work in backup and recovery for a living. I've been doing TSM professionally for the past six years.
So let's look at this idea that portable HD is cheaper and faster. I've managed backup systems that were backing up tens of terabytes every day. Let's say three 3 TB HDDs for the sake of discussion. Let's say five weeks' worth of data retention. That's 5*7*3 = 105 hard drives that need to be managed - call it 110, to take into account the fact that there are going to be a few going off and onsite at any given point in time.
How reliable are those hard drives? How long until they fail? Bear in mind when considering your answer that hard drives are designed to be stuck inside a chassis that stays put (for the most part) - pulling them out of the system and lugging them halfway across town is not within their design goals. And then you need to worry about the cost of a hot-swap chassis so you can pull the drives out, and shove them back in, every day. Oh, and don't forget that most plugs have a limited life span - probably in the hundreds of swaps, maybe thousands (I don't know, and I'm happy to hear solid data about this.)
And how long does it take to fill up a hard drive, anyway? Take the WD Green 3 TB as an example: 110 MB/s (source), equals about 7.5 hours, best case. Sure, you can throw more hard drives at the problem in parallel, but that just exacerbates the whole question about reliability in transit. The Hitachi 3 TB is faster - 207 MB/s - which takes about four hours to fill up. That's best case scenario, based upon the maximum data transfer rate - guaranteed it's going to slow down as the drive fills.
Now consider tape. Consider wikipedia's information on LTO when reading this. LTO4: 120 MB/s native, up to 300 MB/s compressed (two hours to fill). LTO5: 140 MB/s native, 350 MB/s compressed (three hours to fill). Pretty damn reliable in transit; they're designed to sit happily in their little plastic shells, in a box, and get thrown around (not quite, but they can certainly take more punishment than a hard drive can.) Capacity per cartridge: 800 GB/1.5 TB native (4/5); 1.6 TB/3 TB compressed. If you have money to burn, you could go for Oracle's T10000C drive: 5 TB native capacity, 240 MB/s native throughput (and that's before you get into the whole question of compression.)
Now let's get onto the whole subject of financial data, Sarbanes-Oxley, and WORM media (so you know the data hasn't been altered since it was written out) ...
Sure, tape sucks. It has major issues when data is scattered all over the place; mount time takes a while; and the drives need regular love and attention. But here's the thing - it survives today because it's better than the alternatives in its niches, and trust me, there's plenty of niches where tape fits in far better than the alternatives.
If you only have a couple of TB of data to backup, the cost of setting up tape infrastructure will probably not be worth it. But when you're talking hundreds of TB - or better, petabytes of data (don't laugh, one client I did work for had over 2 PB of data in their tape library) - the cost equation swings over pretty damn fast. Tape is not dead. Far from it. I can't see the likes of IBM investing in developing LTO6 and LTO7 if there was no use for it. And why would Oracle sell a tape library that scales to 100,000 slots if there's no demand for it? It's not about how to get the most bytes for your dollar - it's also about reliability, and that gets down to the usage. If I suggested portable hard drives to the clients I do work for, I'd be out of a job - because they simply won't cut it for their needs.