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Backups-Cheap IDE Drives as Alternative to Tapes?
3107813 asks: "Are large IDE drives a good alternative to tapes for backing up a server? I have a server with about 40GB of storage that I backup nightly. I have a tape rotation and end up saving the monthly tapes in case someone comes back and wants a file they messed up. Could I replace the tape system with large cheap ide drives?" The thing that makes tape popular as a backup medium is due to the fact that they are portable. Now that IDE drives are becoming cheaper and smaller, would something like this be practical?
60 gigs, cheap as chips and would do the job
Maxtor DiamondMax 61.4GB 5400rpm 2MB Cache Buffer 8.9ms Access Time ATA-66, 96147U8 Bulk $ 267.95
Imagine one of these in your mp3 jukebox !
Someday, we'll look back on this, laugh nervously and change the subject.
What about the moving parts inside of tapes? I have had countless issues with tapes. The travan cartridges are expensive becase there is a fair amount of mechanics in them! DDS cartridges are cheaper and more portable, but the drives are expensive and (here's the real kicker) TAPE STORAGE TECHNOLOGY ISN'T KEEPING UP WITH HARD DISK TECHNOLOGY!!! These DDS drives are just not big enough anymore.
You say that the math is such that tapes are cheaper, but I challenge you to do the math. A tape drive that is capable of storing 40 BG of storage (uncompressed) will be expensive. The only technology that comes close is DLT. A 35/70GB DLT will set you back about 5 grand! Then the damn tapes are $35 a pop (and, once again, filled with a lot of things that can break)!
Depending on that data (and this is really what backups are all about, huh?), the hard disk option is making more and more sense these days.
Now, where does it not make sense? With my customer. They have a need to have immediate access to data that is up to 5 years old (telecommunincation regulations). We are talking exabytes of data. We have to use these *HUGE* StorageTek silos that are packed with DLT cartridges and drives and controlled by robotics. In this sceneraio moving this data to disk makes no sense and is not econmonical. These guys cycle through 4.5TB of storage every 10 days!!! The biggest issue with tapes these days is the scale that we are talking about before it starts to pay not using hard disks!
I was pondering a few hours ago about this exact issue. My solution will be to get about 4 more disks (for less than the price of a decent tape drive but with a *LOT* more capicity) and keep a mirror handy. Once a week, remove the mirrored disk and replace it with another, sync the mirror, and repeat. For my data, this is plenty good enough. For my customer, forget it.
You speak of "cheapness" as if cost was the deciding factor, but do the math and you will find that tapes are way - way - cheaper per megabyte than hard drives. Not to mention issues of portability and reliability. I don't know, but something about my backups being full of moving parts seems onerous to me.
If you must do it this way, at least stick the drives in a RAID 1 array. You get all the benefits of your backup, except it is always a "perfect" or "realtime" backup instead of a nightly thing because disk writes are written to each disk simultaneously (mirrored). In addition to getting the redundancy of as many disks as you have in the array, you will see a big jump in your read performance (not write, though).
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I think there is a world market for maybe five personal web logs.
If yopu only require one or two restorable regressions, or resorations are frequent, a couple of relativly cheap IDE drives might fit the bill. Of course, at some point of backlog/downtime cost, you'd be better off sticking with tapes.
You can even off-site them easily; IDE pull racks and perhaps a small bootable image (a single floppy) will ensure they're more universally accessable than a tape..
Myself, I use a mix of IDE, tape and CD. IDE gets first gen, tape gets 2-4, and every third fifth gen backup is converted to CDRAID.
.sig: Now legally binding!
I use IDE Backups now, for many of the reaons you know and listed, but the one drawback I can think of is that you cant take them off site. If you have serious data you NEED to protect, and a (fire, flood, dwarf invasion, et.al.) strikes your facility, it could take out both machines and the drives in them... With tapes and the like you can at least take one home with you each week for what we, in the biz, like to call "off-site data storage". Then again, you just just arrainge with the new off-shore data haven to host one of those IDE drives..
Which leads me to my newest venture (and if any of you out there would like to invest, let me know) a Moon-Base for data storage. Where could be better for lawlessness and security. The only thing that could take it out is an asteroid.. Well, that or if the US dusted off its plan to nuke the moon.. In closing: IDE backups are good. Moon-bases are better. -Josh