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Best Home Backup Strategy Now?
jollyreaper writes "Technology moves quickly and what was conventional wisdom last year can be folly this year. But the one thing that's remained constant is hard drives are far too large to backup via conventional means. Tape is expensive and can be unreliable, though it certainly has its proponents. DVDs are just too small. There are prosumer devices like the Drobo, but it's still just a giant box of hard drives, basically RAID. And as we've all had drilled into our heads, 'RAID is not backup.' When last this topic came up on Slashdot, the consensus was that hard drives were the best way to backup hard drives. Backup your internal HDD to an external one, and if your data is really important, have two externals and swap one off-site once a week. Is there any better advice these days?"
I decided that I have three main "categories of data":
- easily replaceable: This is stuff that is fairly easy to replace.. for instance I have ripped a huge portion of my DVD collection (for my own use). If I lost this data, it would not be a tragedy .. just a pain in the ass.
- hard to replace: This is stuff that does exist "out there".. but would not be easy to replace. This includes old TV shows that you can't buy or if you can are very hard to find.
- irreplaceable: Self explanatory.. this is my documents, code, photos, etc that could not be replaced if lost
I keep everything besides OS files on a file server. Raid 6 (two parity stripes).. this is the first layer..
to me this is adequate to protect "easily replaceable" stuff (which in my case constitutes a huge chunk of file space).
I backup everything in the "hard to replace" and "irreplaceable" categories to a seperate (removable but stays in the system) hard disk (so far 1TB has been enough to hold all this data). I make a
secondary backup to a second removable drive and store this "off site". This secondary backup does not get updated very often.. which is the trade off I guess... but it provides a "last hope" if something
crazy ever happened.. like my house burning down.
Oh.. and backups are encrypted!
I think the OP's post arose from a misunderstanding of what "RAID is not backup" means.
The adage isn't an admonition not to use hard drives as a means of backing up data. Rather, it is concerned with the fact that any change to your data is committed to each duplicate volume in a RAID, so if you delete an important file, for example, it's just as gone as if you weren't running a RAID.
That's completely different from mirroring your drive onto an external hard drive and putting it on a shelf somewhere. If you delete a file on your live system, you can restore from that backup.
There are three kinds of data:
1. If you lose this data you will go to jail.
2. If you lose this data, your business will be impacted.
3. If you lose this data, you will have less options for entertainment.
#1 tends to be a megabyte or less.
#2 tends to be a few hundred megabytes of documents.
#3 tends to be terabytes.
My company has a PDF of every document that we've touched in the past decade (federal law requires this retention), and our entire business continuity backup fits easily on four LTO-4 tapes, plus a very less-than-full tape that we rotate for offsite storage weekly. We've explored every backup system out there and this is by far the most cost-effective for us.
I don't understand why the OP claims "tape is unreliable", as I have not heard of a single instance of in-service failure of an LTO-4. As for it being expensive, it is, but before we went to tape we were using Firewire800 external drives, much more expensive than tape cartridges, and not as reliable as some people have been led to believe.
USB and FW external drives almost never fail as long as they are powered on. They fail in storage, which seemed pretty weird to me, since they should be able to sit on a warehouse shelf indefinitely. My low-sample unscientific data from experience says otherwise.
Since everybody is going from LTO-2/3 to LTO-4, you should be able to get LTO-3 transports pretty cheaply.
But my first advice is to identify the data in categories #1 and #2, where you might realize that it's a good practice in any case, to store the important stuff with its own priority. This is the hard part. Identifying what's actually important. If you don't do this, no matter what backup system you end up using, you're going to be burying the important stuff in the noise, introducing risk.
The OP also mentioned Drobo. I have a Drobo and I love it, but I must warn you that it's pretty slow, even with really fast drives. Don't expect to be able to copy a terabyte to it in less than 40 or 50 hours, even with firewire 800. This is the problem that drove us to tape, which is much faster than any filesystem we can feed it from.
-fb Everything not expressly forbidden is now mandatory.
Ghost Virtual Machine gives 15gigs of Amazon.com data storage and right now if you use the promotion code of "launch" you get 10Gigs more as a bonus for 25Gigs. If you want to give me a referral my id is orion_blastar there, and each person you referred grants you 5Gigs more in a bonus.
Google Docs also has document storage but does not give as much as G.ho.st does. The Ghost Virtual Machine can access your Google Docs drive as well.
Here is a review of the top 5 online cloud storage sites so you can take your pick.
MyBloop offers unlimited free storage, but I am not 100% sure of that or their privacy policy.
Lifehacker talks about using your Yahoo Mail account for unlimited storage and also that Google's GMail almost offers the same service as well.
Remember, Slashdot does not have a -1 disagree moderation, and no, troll, flamebait, and overrated are not substitutes.
This is a bad idea. Other than the ludicrous cost of the SSD, flash drives tend to fail all at once. bam! and all your data is gone. This is also why i do not use a USB key for backups.
On my system everything is dumped on a 2TB mirrored system (simple 2 x 2TB HDDs running debian software encryption + RAID lvm) and periodically backed up to blu ray DLs in duplicate. At $10/disk from japan (see ebay) two verbatims back up 50GB in duplicate for $20.
Typically it takes 2-3 months to generate that amount which means its cost effective. DVDRs (Taiyo Yudens) fill the gap if there is not enough data to justify a bunch of blu rays.