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Affordable Home Backups for 10-100G Systems?
MichaelJames asks: "Ok, I have my MP3's streaming, all our digital pictures up, and a file server running on one machine in the basement. What would be the best way to do simple backups of the system and data? Get a tape drive Get a CDRW or DVDRW to backup the MP3 and pics, but use the old Zip drive for the file server data?" With drives in the 10-20 gig range only getting smaller and less expensive, what are we to do for backups, that have yet to scale well in the same range. For home systems with up to 100G of storage, what do you use to back up that much data, with a solution that's affordable to the average computer user? Have DVD writers become cheap enough for serious consideration as a backup media?
Given that a 100G hard drive is cheaper than any removable media solution, why not just buy another hard drive and install it in a removable (not hot-swappable, just removable) rack?
Racks are $20 at my local Fry's, and inserts for other hard drives are $10.
I have to say that this is coming from someone with a total of around 280gig at the house, but...
Out of 100gig, how much do you really NEED to back up?
The vast majority of my space is taken up by MP3s (where I converted my CD collection), but that could easily be replaced. To tell you the truth, of the things that I would need (documents, pictures, etc), I could easily fit it all onto a CDR. Well, maybe two. (I take lots of pictures)
Basically it boils down to, do you really need to shell out the money for that extra drive?
:^)
'Life is like a spoonful of Drain-O, it feels good on the way down but leaves you feeling hollow inside'
I once worked at a place where we had a lightning storm. Within a week, about half of the hard drives had failed, out of about a dozen. RAID won't save you then. And how fast can you get replacement hard drives installed, anyway?
All the affected machines were plugged into good UPSes, too.
Moral of the story: Always use offline backups.
Why are you bothering to back up your data?
/` or a virus)? If so, then a RAID solution is useless.
That may seem like a stupid question, but you need to consider the reasons you want to have a backup before you settle on a method.
Are you afraid of your drive failing? If so, then using a RAID solution should cover you.
Are you afraid of losing your whole system (perhaps due to lightning or theft)? If so, then your backup must be kept physically isolated from your system.
Are you afraid of accidentally deleting files (such as `rm -rf
Are you afraid of having your system down for an hour or two while you replace a drive? If so, then regardless of other issues, you need a RAID setup.
Do you want to use your MP3s with some other device? If so, you probably want CD-R copies.
Of course, there are other considerations that I haven't mentioned or thought of.
Not to distro-bait, but Debian in particular shines here because apt makes it so damn easy to bring a system back to the state you wanted. For myself I have created a meta-package (.deb) which does nothing but depend on the applications I want installed on every desktop system: galeon, gnucash, xchat, gaim, xmms, vim-gtk, and a handful of others. Then I back up my meta-package, all of 10k including a few shell scripts I wrote for myself. Install my meta-package on a new system, and voilá, apt fetches and installs every app, that I need to continue working, dependencies included.
It's rare that you're presented with a knob whose only two positions are Make History and Flee Your Glorious Destiny.
RAID is to provide either additional speed and/or hotswappable capability. RAID really stinks as a backup, since RAID doesn't care when some program deletes most of the hard drive, when some user removes too many files, or when the OS barfs. Sure, RAID will save your DATA if one HDD fails, as long as whatever caused it to fail didn't affect the other drive, but for the reasons already listed, this doesn't mean RAID is a valid method of backup.
However, a HDD in an external enclosure could be considered a valid backup, however, for true redundancy, you better have two drives you swap, and you better be doing surface tests regularly. A drive, properly treated, should last many, many years. Also, you could combine a drive with monthly or quad-yearly backups to CD-R, just make sure you do your research on the inks used in CD-R disks, some don't last as long as others.
Just my $.02
That worked really well for backing up our 80MB drives onto stacks of 1.44MB floppies, since you would really only need to insert about 5-10 floppies during your weekly backup, just to get the files that changed.
So why not just do incremental backup onto CD-Rs? Even with 100GB of archives, most of those are static. You probably won't need to use more than one CDR per week (maybe two) to track the changes. It's cheap, relatively painless if you've got the right software (and it wouldn't be hard to throw together incremental backup/recovery scripts in Perl if you're into that sort of thing.) and you've probably already got a CD burner.
If less than 650MB of files change in a week, the rest of the CDR can be filled up with files that were on earlier CDRs (this way your backup set can remain finite and you can throw out the earlier CDRs as they become obsolete. Or if you keep them all, you can reconstruct that state of your hard drive at *any* time, not just at the last backup.) This seems ideal to me--why is everyone else talking about expensive solutions like tape drives, DVD-RWs, and second hard drives?
I have a positive modifier on Troll. When I mod someone Troll their karma should go UP!
I have to wonder whether (first of all) why in the heck anyone would need to have 100GB of disk space on a home system. But then I have five systems networked together and have more storage than I would have thought sane a few years a go though I have a bit of a ways to go before I will run into the poster's backup problem. It wasn't too long ago that, if you could afford 100GB, you could probably afford a SCSI array controller that would let you do a lot of RAID, hot swapping, automatic drive replacement, etc. With today's cheap disk prices you don't have to be wealthy to have an ocean of disk space. (I can remember the days when we thought having 900MB on a MicroVAX II was extravagant.)
You could always do it the traditional way and get some tape drives. Unfortunately, they're much more expensive than you might think when you have to backup that much disk space. You certainly wouldn't want to go cheap and be feeding 90m DAT cartridges into a drive all night (it'll start feeling like you're backing up to floppies before long). A good high capacity tape drive can get, what, 20GB onto a single cartridge? Not bad. And I think that at this point in time, tape is more cost effective than DVD-R. (Something tells me that the MPAA, and maybe the RIAA, will try to keep it that way too.)
Mirroring disks can be helpful. Hard disks are getting cheaper and cheaper. Heck it's almost scary mow much disk space you get in a typical PC sold at Best Buy nowadays (and without a backup device; it's almost criminal). If you're running mirrored disks you'll forestall the inevitable disk crash that takes all your data with it. Question for the Linux folks using the `md' driver: Does it allow adding a third member to a mirrorset? And, if so, can it be done while the system is `live'? (The third member gets removed and taken offsite in case there's a disaster.)
One final thought: The poster wasn't actually running a 100GB filesystem were they? I'm thinking that a power glitch could cause a world record to be set for the longest fsck-on-reboot run. Plus I'd think that backing up such a beast would be a challenge. I tend to keep my filesystem sizes no larger than what I can fit on a single tape cartridge... just to make life simple. (I'm used to having to pipe `df' commands through `more' at work so I don't mind lots of mount points. :-) )
CUR ALLOC 20195.....5804M
True -- but given the article's "affordable", "home", "10-100GB" parameters, I'd be quite happy regarding hard drives as a real solution.
Don't expect one hard drive to last you 10 years, because 10 years from now, systems with 40-pin IDE won't exist. (And likewise, neither will readers for the tapes you purchase today. When was the last time you saw a DC600 cartridge tape drive available?)
If you're talking longterm storage, leave your "backup" drive somewhere secure, and expect to replace it every 3-5 years. (That'll probably be a 500G serial IDE drive 5 years from now, a terabyte-range solid-state device 10 years from now, and a petabyte-range holocube 20 years from now.)