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Hard Drives Instead of Tapes? 484

Posted by CmdrTaco from the why-the-hell-not dept.
An anonymous reader writes "Tom's Hardware News weekly news letter has a very interesting article about Dr. Koch of Computertechnik AG who won the contract to build a RAID backup system for the University of Tübingen. Dr. Koch took several standard entry-level servers, such as the dual-Athlon MP, and add modern components and three large-caliber IDE-RAID controllers per computer, and a total of 576 x 160GB Drives."
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Hard Drives Instead of Tapes? More

Hard Drives Instead of Tapes?

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  • Far more practical (Score:5, Interesting)

    by Random BedHead Ed ( 602081 ) on Thursday April 24, 2003 @02:24PM (#5802127) Homepage Journal

    This is a much better solution than tape, really. It's predictable that the industry will probably move in this direction, now that the hardware is cheap enough and of high enough capacity to serve this function.

    Imagine: instant recovery. Your backup could be a usable image of your live server.

    • Re:Far more practical (Score:5, Informative)

      by diverman ( 55324 ) on Thursday April 24, 2003 @02:30PM (#5802194)
      Yeah, I've seen this trend for a while now. Our backup system is also a large HDD raid setup. And for things that need long term storage, those eventually get spooled to tape. I'm sure long term storage will probably start going the way of DVD optical media or something similar (better capacity more likely).

      Yeah, the full usable image would be nice, but would probably require a shutdown for data consistency. The backup strategy would likely be similar to that of an Oracle system cold backup. :)

      -Alex

      • Re:Far more practical (Score:5, Insightful)

        by Random Frequency ( 34459 ) on Thursday April 24, 2003 @03:08PM (#5802626)
        cdr/dvdr uses a chemical substration process to have data written to it, and is nowhere near as stable as magnetic tape.

        • Re:Far more practical (Score:4, Informative)

          by shotfeel ( 235240 ) on Thursday April 24, 2003 @03:39PM (#5803046)
          The reported shelf life for CD-R is anywhere from 10-100 years depending on the type of dye and who you want to believe.

          My understanding was that for tape it is only 5-10 years, but that could very well be out-dated. What is the current shelf life for magnetic tape?

    • Re:Far more practical (Score:5, Interesting)

      by Servo ( 9177 ) <dstringf@@@tutanota...com> on Thursday April 24, 2003 @03:08PM (#5802620) Journal
      I don't really see it as being all that predictable.

      The benefits of having backup to disk is of course speed. But what happens when you have a disaster? Your SOL, because your backup-on-disk system just got toasted too.

      The benefits of having backups on tape is that you can send those tapes anywhere. It might not be as quick as sending a file electronically, but when you are talking hundreds of gigabytes of data, it just isn't economical to do anything but tape.

      Tape will never die. Hardware may be cheap and high capacity, but transmission costs keep it from being feasible.

      You also need to take a look at space utilization. You can put a tape silo into a footprint that gives you much much more capacity per square foot than disk.

    • Re:Far more practical (Score:5, Interesting)

      by jhoffoss ( 73895 ) on Thursday April 24, 2003 @03:16PM (#5802747) Journal
      This concept raises some issues though. My employer owns two +1TB SANS and has them in separate locations, constantly mirroring from the production to the backup. But if you delete a file off of one, it is also deleted off of the other. So then how do you decide when to actually delete something from the backup, if you want it to serve as a tape backup? Other anomolies can occur as well. A drive died in our backup SAN which brought both SANS (and in turn, all of our servers, which run off of the SAN using fiber cards) to their knees immediately, because they were trying to write bits to that drive (big coincidence, but took us down for over two hours, and it could've been much longer than that...) Still, an interesting concept. But we still take tape backups daily, incrementally through the week and a full backup over weekends. Never put all your eggs in one basket, remember.

      • Re:Far more practical (Score:3, Interesting)

        by amorsen ( 7485 )
        Mirroring is not backup. If you want to do backup with disks, treat them like tape. Tar up the files, put them on the disks. Reuse disks over time, just like tapes. For backup, the only difference between a disk and a tape is that with a disk it can be really fast to skip to a specific file or archive.

        The perfect solution to backups would be notebook SATA disks, which should hopefully appear soon. Hotpluggable, no bulkier than an LTO or DLT tape, screaming fast compared to LTO and DLT, and very hard to dam

  • Compliance (Score:2, Interesting)

    by sk3tch ( 165010 )
    So a BIG RAID is somehow safer than many small RAIDS? Backups aren't just for the heck of it...some of them are required for compliance, i.e. the financial industry.

    • Re:Compliance (Score:5, Insightful)

      by Havokmon ( 89874 ) <{moc.nomkovah} {ta} {kcir}> on Thursday April 24, 2003 @02:43PM (#5802344) Homepage Journal
      Backups aren't just for the heck of it...some of them are required for compliance, i.e. the financial industry.

      Oh PLEASE! I worked for, what was at the time, the 17th largest CC processor in the nation. Not so big, but lots of merchants. They bought a front-end (where your credit card terminals dial into), and built a backend settlement (so they didn't need FDR - who recently ROYALLY hosed everyone with a software update, including CHASE themselves. No, this software update was completely seperate from the SQL Slammer worm that took them down when it appeared.).

      Complaince, usually done by the OTS (Office of Thrift Supervision), is NOT ISO 9000 type stuff. Financial companies are CHEAP. Never forget that. Whatever is the cheapest solution, is the one that is used.

      As for tape backups - as an example: It took quite a bit of convincing to upgrade from the 4 drives that took two days to backup the whole network to a single Sont DLT drive. (Because $70/tape is a LOT of money)

      There were no 'compliance' worries at all.

      • Oh PLEASE! I worked for, what was at the time, the 17th largest CC processor in the nation.

        That's not the financial services industry in any meaningful sense of the word, just a teeny tiny corner of it. If you're trading real instruments - think Wall Street, or the Square Mile - you need to keep everything around for 7+ years, and if anyone you've traded with in that time gets audited, you might be asked for your counterparty records. Not to mention the fact that you can trade instruments with a maturity

    • Re:Compliance (Score:2, Insightful)

      by stilwebm ( 129567 )
      Those aren't just backups, but also archives for auditing purposes. The analyist scandals of the last couple of years really helped drive home the need for these archives.

      They of course are also important for business continuity, as Sept. 11, 2001 showed us when several large finacial firms had their data centers destroyed.

  • Sound fine, but... (Score:2, Insightful)

    by Quasar1999 ( 520073 )
    What about being able to transport and store the information offsite?

    I mean, sure tape isn't great, but it's a lot more transportable than harddrives.

    • Re:Sound fine, but... (Score:5, Informative)

      by ashitaka ( 27544 ) on Thursday April 24, 2003 @02:28PM (#5802173) Homepage
      I don't know about the mega RAID systems descibed in this article but we're doing this with a couple of high-capacity IDE drives in a removable drive cage. The relevant system states and data are backed up to these drives daily. The time to get our databases and files up to running state in a disaster scenario is under three hours.

    • With the huge size of some databases, it would make more sense to connect to your offsite storage via fiber and store it there. There is no reason the backup disks need to be in the same room or building or state as the primary disks. Then you also solve the problem of reliably getting the data offsite in the first place. This is of course more expensive than renting a storage locker and driving a dat tape over to it every night, but I don't think Citibank is driving too many tapes around town. (just a gu

    • Re:Sound fine, but... (Score:5, Informative)

      by afidel ( 530433 ) on Thursday April 24, 2003 @02:37PM (#5802269)
      Well as the article states this implementation isn't really for offsite There's one aspect in which Dr. Koch's backup system can't keep up with tape solutions: storing the backup medium in another location after the backup has been completed. but it could be done pretty easily. Non-operating shock capacity on the D540X is 300G's for 2ms which is pretty darn good (plastic tape housings might shatter under a similar load). I also like the ultra low failure rate .5% (hmm, this and the data from storage review shows that the D540X and D740X line seem to be some of the most reliable out there...) I know our DAT failure rate was in the same ballpark.

    • Re:Sound fine, but... (Score:5, Informative)

      by Bonker ( 243350 ) on Thursday April 24, 2003 @02:41PM (#5802306)
      As someone who works in IT in the financial industry, let me tell you a little bit of what kind of requirements we fulfill. First of all, every system is backed up on a regular basis. For critical systems (systems that handle account numbers in any way), that schedule is daily or even hourly.

      All systems have live fail-overs. When not required by law, and they frequently are, such systems are required by the demands of profit. If financial transactions falter for a *second*, it means money lost.

      Back-up media is triple redundant and incremental over 5 days. Backup irregularities of any kind are logged, investigated, and acted upon by at least 3 individuals.

      Copies of backups are stored both on site and off-site in a secure location provided by our insurance provider. We make frequent trips to this secure location daily in order to deposit backups. These procedures are audited and reviewed on a regular basis by both internal auditors and regulatory board auditors.

      Tape is just a little more reliable than IDE in this kind of situation. Tape is going to be more recoverable, even in case of a long drop or serious auto accident between point A and point B. If necessary, teap will also survive shipping better.

      Sorry, guys. As reliable as IDE drives have become, they're just not as durable as a tape cartridge. With the sheer amount of backup we keep, it's also significantly cheaper.

      • Re:Sound fine, but... (Score:4, Insightful)

        by GigsVT ( 208848 ) on Thursday April 24, 2003 @03:12PM (#5802669) Journal
        Why do people in industries with strict uptime or reliability requirements always act holier-than-thou about the whole issue, as if their way is the only right way?

        Not all companies need five 9's. Not all companies lose much money if data or systems are not available for a short time. In fact, I'd say it's the majority of companies that fall into that category.

        Extreme reliability and availability are extremely expensive. For most companies, it's not worth it.

        I agree with you, Large ATA RAID probably isn't for your industry, it's not right for everyone. It does work fine for lots of people though. I expect to see it cover much of the 5TB range of near-line backups in the next few years.
    • You can kinda do the same thing, albeit slower, using something like rdiff-backup [stanford.edu], RAID, and a fast network.

      I could envision a super-fat pipe being used to mirror a facility to a neighboring (or even geographically-distant) facility along with a system like this.

      rdiff-backup saved me when a power supply blew out on a server. Within an hour of the failure, I was back up and running on the backup server. It could have been much faster had I automated the failover...

    • High end mag tape cartridges store 50GB. One hard drive can replace three tape cartriges. When sending the drive off site for storage, just use the same box you used for the tapes and fill the extra space with shock absorbant padding.

      But wait there's more. Those mag tape cartriges have a transfer rate of about 10 MB/sec. With hard drives, your backups will take a fraction of the time they took under the old system. That leaves plenty of extra time to pack the drives up extra securely. You may even be

      • Re:Sound fine, but... (Score:5, Informative)

        by Zathrus ( 232140 ) on Thursday April 24, 2003 @03:04PM (#5802577) Homepage
        High end mag tape cartridges store 50GB.

        Uh, I think you better look at tapes again. AIT-3 is 100GB uncompressed. Super-AIT is 500GB uncompressed. Transfer rates for Super-AIT are in the 30 GB/s range uncompressed. All of these numbers go up with compression, which is built into the tape drive hardware -- assuming you're storing compressable data.

        All in all, they're likely to have a higher sustained transfer rate than IDE drives, and are going to be more reliable, less costly in bulk, and easier to handle.

        Of course they're silly for small systems... but that's not what we're talking about at all.
      • No the current high end tape solution stores 500GB natively and over a TB compressed (Sony Super AIT). With SDLT at 160GB native 320GB compressed. Transfer rates for both are around 30MB/s native 60MB/s compressed. Your data sounds like old DLT IV numbers (admittadly those are probably the majority in use). This is for cartridge style solutions, reel to reel are even larger capacity.

  • I don't know if that is a good idea (Score:4, Insightful)

    by Tighe_L ( 642122 ) on Thursday April 24, 2003 @02:26PM (#5802147) Homepage
    There has to be a better way than relying on anything stored in magnetic format, optical I think woudl be preferable, and resistant to EMP.
    • Yeah damn that EMP... If a neutron bomb goes off, I sure as hell don't want to lose my 100+ TB pr0n collection.

    • Re:I don't know if that is a good idea (Score:4, Insightful)

      by csnydermvpsoft ( 596111 ) on Thursday April 24, 2003 @02:37PM (#5802265)
      Storing data offsite is the only good way - even optical media is still vulnerable to a nuclear strike.<g> Of course, if you get nuked, your backups will probably be the least of your concerns.

      The best backup solution would be a bunker with hard drives, backed up via fiber in real time.

    • Haven't you ever put a CDR [pan-tex.net]in a microwave [knoware.nl]? Pretty lights! (I take no responsibility for any damage to your microwave...)
    • There has to be a better way than relying on anything stored in magnetic format

      We could punch into paper tape.

    • Re:I don't know if that is a good idea (Score:5, Funny)

      by angst_ridden_hipster ( 23104 ) on Thursday April 24, 2003 @03:04PM (#5802587) Homepage Journal
      Etched stone seems to have a staying power of approximately 10,000 years, even with some outdoor exposure.

      Earthenware tablets, made of clay fired at low temperatures (1816F/991C), seem to do nearly as well, while stoneware tablets, made of clay fired at high temperature (2345F/1284C), last about the same as actual stone. Ceramics have relatively high resistance to moisture and thermal variation. Depending on the clay composition and the application of glazes, there is variable resistance to acid. Ceramics do not handle physical shock particularly well.

      Glass can last thousands of years, but is vulnerable to shattering or acid.

      None of these, however, are earthquake-resistant. Outside of the immediate blast radius, they're good against nukes.

      Etching into stainless steel is good, although in the event of a nuclear attack, this would be succeptible to melting (or self-destruction due to induced current) within a certain area. It handles thermal and moisture extremes pretty well, but doesn't handle acids well.

      Stamping into gold foil is expensive, but quite durable. It's immune to some of the chemical risks posed by steel, but is more likely to be stolen. It's also not as hard, thus leading to risk of data corruption or loss via impact.

      Parchment, preserved lamb or sheep skin, can last a very long time (on the order of 2,000 years) in the right conditions. It does well with exposure to electromagnetic radiation, but deals badly with moisture or excessive dryness, and is highly vulnerable to acid.

      Delay-line broadcast (reflecting your data with a laser off of a distant object, and rebroadcasting ad infinitum) is fairly reliable until occlusion of the data path occurs, or the transceiver is smashed, unplugged, EMPed.

      Yeah, data preservation is hard in the long haul.

      • Re:I don't know if that is a good idea (Score:5, Funny)

        by belloc ( 37430 ) <belloc@@@latinmail...com> on Thursday April 24, 2003 @03:59PM (#5803281) Homepage
        Etched stone seems to have a staying power of approximately 10,000 years...

        This reminds me of a formal budget proposal submitted by my predecessor many years ago (I run the IT dept. at a small college). He gave a very detailed cost breakdown of several means of replacing our then-current backup and recovery method for our file server's RAID array (we were very small way back then). He had costs for hardware, time, and manpower for just about every option available at the time.

        His last option, put forth just as seriously and fully as the rest, included the cost of having a team of monks write out the data by hand onto reams of paper, bit-by-bit. Then for recovery, the monks would re-enter the data back into the computer, bit-by-bit. On the pro side he argued that monks work cheap and are very dedicated to what they do. But the con was the time involved for this method was somewhat prohibitive. ;)

        Belloc

  • This would work for limited installations (Score:3, Insightful)

    by Anonymous Coward on Thursday April 24, 2003 @02:26PM (#5802151)
    But as large as harddrives are getting, the demand for backup will still be larger. I don't see this as taking over tape any time soon. People have been talking about how big harddrives are getting and about the demise of tape for a long time.

    Just remember, if you can build something like this for backup, you can also build something like this for regular storage... and then what will you do if you need to back it up? Especially if you need to have a 6 month rotating backup...

    I'm afraid it will be back to tape then...

    • Except tapes are more expensive than comparably-sized hard drive arrays. Just get a bigger hard drive array.
    • What we need are really big lasers.

      With a sufficiently powerful laser, you could encode the data and beam it off to some distant object. When the reflected beam finally reaches earth, there is your backed up data, ready for retrieval. You could pick a number of objects at varying distances to allow for longer backups of data, with reflection times of hours/days/weeks/years... Granted there would be some celestial issues that could corrupt your data, but if you picked a few redundant yet diverse backup site
    • The problem isn't really related to duplicating the active on-line data, but protecting your information from a number of forms of system level problems. The truth is that tape, and off-line backup technologies generally, really sucks for disaster recovery (DR), mostly because there will be a lot of manual operations and rarely tested procedures involved.

      Data probably is corrupted much more frequently by mistakes and systems problems, and with the sort of live redundancy favored by DR architectures the b

  • Surprised it didn't happen sooner (Score:5, Informative)

    by Dragonfly ( 5975 ) <jddaigleNO@SPAMmac.com> on Thursday April 24, 2003 @02:27PM (#5802164) Homepage
    I know of a lot of people (myself included) who use multiple external hard drives in rotation for their backups. Especially now with servers' hard drive capacities growing so fast. I just specc'd out a fileserver for a department at a cash-strapped public institution, and a tape drive big enough to backup the system's disk would have been more than 50% of the cost of the computer. Not to mention the cost of tapes. Instead I set them up with two firewire hard drives. For their needs, the reliability/longevity/cost equation made hard drives the best solution.
    • The adta on the hard drive is suseptiple to both mechanical failure and media failure.
      With tape, if the reader fails, you will probably still have your data, and you can just find another reader.
      I would also like to point out that HD manufactures our lowering there warrenty period. IT is only a matter of time before some cost cutting measure makes them use lower quality equipment and parts.
    • Don't be - it did. Mainframers have been doing this for years. No...decades. They just do it better - disk as a backup or as a staging area for later writing to tape.

      The staging solution has been available (fully automated) in Unixland for at least ten years.

      Disk backups are fine for on-site backups but you still need off-site copies, which is done either by tape or over-the-wire synchronizing. The latter gets real pricey real quick.

  • Offsite? (Score:5, Insightful)

    by da' WINS pimp ( 213867 ) <dart27@gm[ ].com ['ail' in gap]> on Thursday April 24, 2003 @02:28PM (#5802170) Journal
    One thing about tape systems that I didn't see mentioned was the portability of the media. Data recovery is still impossible if your backup burns up along with your server. I don't see anyone rolling one of these out to the offsite storage.

    Maybe you could do it with a big pipe between your backup location and your servers. But I bet that would cost a bundle in bandwidth.

    Also did anyone notice that typo on UPS (maybe they were on drugs USP [usp.org])! It took me a good minute to catch it.

    • Re:Offsite? (Score:3, Insightful)

      by jandrese ( 485 )
      That depends how "offsite" you want it to be. A fiber run across campus (say about a mile away) isn't too bad and can easily be Gigabit speeds.

      I've been using HDDs for backup for awhile now. Tapes were just way too much hassle, too expensive, and too fragile for my daily backups. I don't have protection against fire, but the whole setup can backup 650GB (usable) of data, survive disk failure, and cost me $1500, and I built this a year and a half ago with 80GB drives. My nightly backups are fully aut

      • Re:Offsite? (Score:3, Interesting)

        by afidel ( 530433 )
        Good point, he does talk about 100 nodes, why not have them on seperate ends of campus or even across town. Using longhaul fibre adapters they could go up 16 miles I believe without a repeater. So just devide the nodes into two groups and mirror the data to both sites, still be cheaper than tape. Sure it wouldn't work for a multinational corporation (for instance the telephone and transmitters in NY were often mirrored by being in each of the twin towers, this is now seen as being "not a good idea") but any

    • Re:Offsite? (Score:5, Interesting)

      by kiwimate ( 458274 ) on Thursday April 24, 2003 @02:41PM (#5802310) Journal
      Well, they kind of flitted over it with one sentence:

      There's one aspect in which Dr. Koch's backup system can't keep up with tape solutions: storing the backup medium in another location after the backup has been completed.

      The article didn't address what to do in this case. Instead, they continued:

      As long as this isn't necessary, Dr. Koch's backup system offers some rather unique advantages.

      Given that it's hardware-focussed, maybe one can understand this omission, but here in the real world it's still important. So, yes, what does one do if one does need offsite storage? Realistically, I think your suggestion of a big pipe is about the only way. It's hardly feasible to hotswap loads of drives for your offsite storage every morning. (Yes, I know they're using IDE, but think Promise controllers.)

      The question then becomes a comparison of the cost of providing for offsite storage in this manner versus the saved cost of replacing your tape library with associated robots, etc.

      However, the article also discusses (very briefly) associated costs for specialized backup administrators, delays inherent in recovering from tape backups, etc., so they're not totally unaware of the real-world issue. I suspect they may have chosen to ignore this specific issue because (i) it wasn't an issue in this case study, and (ii) examining it would've been a touch difficult.
    • Maybe you could do it with a big pipe between your backup location and your servers. But I bet that would cost a bundle in bandwidth.
      Maybe not: they could get a 1000-baseFX (or faster) line just between the remote and the main site, and as it doesn't connect to the Internet at large, it doesn't cost a penny in bandwidth, only operating costs to keep the fiber running. In addition, it would be more secure anyway (duh, since it's not connected to the Net at large...)

  • Help me understand... (Score:5, Insightful)

    by sphealey ( 2855 ) on Thursday April 24, 2003 @02:28PM (#5802174)
    There's one aspect in which Dr. Koch's backup system can't keep up with tape solutions: storing the backup medium in another location after the backup has been completed.

    As long as this isn't necessary, Dr. Koch's backup system offers some rather unique advantages.

    Out of curiosity, what is the use of a backup that is not periodically rotated off-site? And by "off-site" I mean at least 50 km away? What happens when a tornado takes out the building holding the critical data AND the building holding that nice array of IDE drives 2 minutes apart?

    sPh

    • What happens when a tornado takes out the building holding the critical data AND the building holding that nice array of IDE drives 2 minutes apart?

      torados are quite rare in Tübingen ;-)

      however, a backup system like this protects you from (accidental) deletion of files and hardware failures. thats enough for many people..

      • torados are quite rare in Tübingen ;-)

        Given that I live in Tornado Alley, I may be a bit sensitive on that topic!

        However, three years ago I was visiting a number of my (then) employer's sites worldwide and there was a disturbing tendency for there to be a severe thunderstorm with tornado while I at a site - some in places where tornados are typically seen only once every 100 years. So don't be too sure!

        But floods, large fires, or some sort of large-scale natural disaster can happen anywhere. Floodi

      • Are fires also rare? What about earthquakes, mudslides, floods, terrorist attacks, or anything else that can effectively destroy a building?

        however, a backup system like this protects you from (accidental) deletion of files and hardware failures. thats enough for many people..

        Well then the spec'd system is vastly overdesigned for THAT. There are far easier ways to solve both.

        It is possible to do off-site storage with drive arrays, but you have to design it into the system. As it is, this system solves

    • Off Site Backup +/- (Score:4, Insightful)

      by 4of12 ( 97621 ) on Thursday April 24, 2003 @03:07PM (#5802609) Homepage Journal

      Offsite backups, whether tape or disk, present some pros and cons.

      Pro: offsite is safer from local disaster effects.

      Con: data restoration takes longer from further away.

      Pro: high bandwidth connection makes moving data quick enough.

      Con: high bandwidth connections are expensive

      Con: high bandwidth connections are susceptible to disaster induced interruption

      Overall, though, I like the random access provided by disk drives over linear searches of tapes. In case the network connection is broken to the backup site, you can easily load a couple of terabytes on cheap IDE drives into the back of your station wagon and bring them to any site you like and the effective BW will still be pretty darn good.

      If you drive your station wagon across the continental U.S loaded with 3 TB of IDE drives in 3 days then you will be running faster than T1.

      safer away from local disaster access time is high when locals need restoration big net pipe to far away but disaster that kills the network pipe ? maybe hard drives can be couriered back.
    • Out of curiosity, what is the use of a backup that is not periodically rotated off-site? And by "off-site" I mean at least 50 km away? What happens when a tornado takes out the building holding the critical data AND the building holding that nice array of IDE drives 2 minutes apart?

      Then you're probably out of business anyway, so what does it matter at that point?

      • Then you're probably out of business anyway, so what does it matter at that point?

        I'll reply to this message, but cover several similar points.

        First, I should note that I do consider sanity checks and cost/benefit analysis when making backup/recovery plans. So I agree with many of these comments. BUT...

        (1) Disasters happen more often than people expect. And they can happen to you, not just the other guy. Wildpackets almost went out of business [eweek.com] as a result of underestimating that.

        (2) Being out of b

  • But how the heck do you take it offsite? One of the most important aspects of a good backup solution is to implement DRP's (disaster recovery plans), and those always include offsite storage. Many companies use third-party services for this purpose (basically a secure controlled tape storage facility).

    So how do you do this in this scenario? I hope they have fantastic fire extinguishers.

    • They've got this great thing called the Internet now.

      And don't trifle me with complaints about bandwidth. Use rsync. If you're really generating so much new data every day that rsync is infeasible, then maybe you have to look at a different solution. But then tape probably isn't your answer, either.

  • uh huh (Score:2, Interesting)

    by hotrodman ( 472382 )

    So, I come in, hit the systems with a hammer, and you're done. A virus wipes you out. A malicous hacker, a stupid user, kernel oops that fucks up the filesystem, something. No tapes to go back to. Not to mention that old data that isn't being used can be archived off to tape, which may end up costing less in the long run that more and more hard drives - hard drives use power, remember?
    I never understand how you can trust you data to ONLY be on media that is tied to the mechanism. If the mechanism

  • HDD Tapestream (Score:2, Funny)

    by termos ( 634980 )
    Hard drives are faster
    Tapes are expensive, HDDs are cheap in comparison
    My C64 uses tapes, I don't even see the competition between these two.

  • Tape technology not keeping pace... (Score:4, Informative)

    by jafo ( 11982 ) on Thursday April 24, 2003 @02:33PM (#5802222) Homepage
    The unfortunate thing is that tape technology just hasn't kept pace with disc technology. Back in my first job, we were backing up $1,000 20MB drives onto $40 200MB tapes. If that held true, today we would have $4 tapes that would hold around a terrabyte of data...

    But, we now have $100 tapes that hold as much data as a $100 hard drive.

    We switched over to hard drives for our backups at our (modest) server facility. Late last year we spent $2000 on a system with 600GB of RAID-5 protected storage. That holds current and historic backups, for around 6 months with our current load. We then weekly dump the current data-set off to a removable 120GB hard drive, which we take off-site.

    Tapes are SO dead...

    It works great.

    Sean

    • Re:Tape technology not keeping pace... (Score:5, Insightful)

      by sirwired ( 27582 ) on Thursday April 24, 2003 @02:43PM (#5802346)
      No, you have $150 tapes that hold 1 TB of IT data. They can be written to at 60MB/s. Tape is compact, requrires no power, it is light, transportable and sturdy. The only major drawback as a backup method is the cost of the drives. (Which gets paid off quickly.)

      To backup a storage pool with under a couple of TB of storage, tape is indeed stupid. If what you need is truly massive amounts of storage that does not need to be accessed instantaneously, tape cannot be beat.
    • Man, I wish I could be there when someone drops a hard drive.

      And what happens when your raid card gets flakey and begins to write garbage data? what if that happen on day 6 of your 7 day back up cycle?

      Some larg instiution need backups in the terra byte range, and they need some data back-ups physically seperate from other data.
      And they want to automated. and off site every day. Hard drive solution will not work.

  • Tape will be with us for a while yet... (Score:5, Interesting)

    by sirwired ( 27582 ) on Thursday April 24, 2003 @02:33PM (#5802231)
    Right now, Sony is shipping Super-AIT tapes. The cartridges are about 3/8 of an inch thick, and each holds 500GB, before compression (which is integrated in the drive hardware). The drive can read or write at 30MB/s, before compression. With typical IT compression of 2:1, you get just under 60MB/s. The cartridge goes for about $150. Just try and get a terabyte of disk for that much. No, the drives aren't cheap, but they get paid off quickly.

    Yes, disk is good if you need instant access to your backup, and for small installations of under a couple of TB, using disk backups make sense, but for larger data pools, tape is far more economical.

    Also, as mentioned in the article, disk is terrible if you need off-site backups. In addition, a tape library consumes far less power, takes up less space, and produces less heat than a drive array of the same capacity.

    Basically, the death of tape has been predicted for years, but it hasn't happened yet.

    • Re:Tape will be with us for a while yet... (Score:4, Insightful)

      by sirinek ( 41507 ) on Thursday April 24, 2003 @02:39PM (#5802289) Homepage Journal
      Right on. :) Most ./ers dont know anything about enterprise systems. Thats why you see them rail against commercial unices, because they only know Windows/Mac/Linux/*BSD. This carries over into tape backup strategy. They dont know anything about high-end tape technology, so you will see them suggest things like using large IDE harddrives because it sounds so simple on the surface. To do backups to disk right (and then to tape, because you really should) you need a real SAN though.
    • The advantage of backup to nearline disk is the near-instant access times for restores. You don't have to wait for a tape to load, and the read speed can be 50 megabytes/sec or higher if you use striping (RAID0,0+1,1+0,3,5) with multiple disks.

      On the down side, you need to keep spinning a disk in a RAID environment to make sure the data is still good. Drives with one-year warranties aren't designed to sit on a shelf for 5 years and be powered back on. When drives fail, the RAID takes over and rebuilds

  • ack! (Score:5, Insightful)

    by mhatle ( 54607 ) on Thursday April 24, 2003 @02:34PM (#5802240) Homepage
    I looked at doing something similar (but on a smaller scale) for my home.. but the amount of power that a hard drive based storage system takes is amazing. In additional IDE hard drives arn't know for their reliability.. :P (I've had numerous IDE raids fail spectacularly to the point I won't do that again...)

    I ended up going on ebay and getting a StorageTek 9714 "Media Library" with 2 DLT 4000 drives in it. It takes a maximum of 2A of power.. (I've measured it much lower then that when the tape drives arn't in use..) This sucker will store up to 2.4 TB ( 1.2 TB uncompressed) in the 60 available tape slots..

    The electricity saves more then makes up for the cost of the tapes.. (Also I expect the tapes to last approx 5-10 years.. I wouldn't expect that with the hard drives.)

    --Mark
    • Did you read the article, 0.53% failure rate for their hdd's and 0% failure at the node and system level. RAID5 + hotspare is pretty damn good at protecting data assuming you have reliable clean power. Look into what it costs to get a storagetek that can handle 100's of TB's and then compare to the less than half million spent on this system. Then add in admin time, training, and the additional time backups and restores take. I think that this type of backup system is really going to take off over the next
      • I IDE raids that I have been involved with all failed in approx 2 to 3 year time frames.. (before the official warrantee was up mind you...)

        The failures generally happened to multiple drives within hours of each other, rendering the raid 5 invalid and corrupting tons of data.. (which of course required the restore off a more perminant media... DLT tape.)

        I'm not saying they could have gotten a backup system for the same amount of money using convential DLT tapes and media libraries.. however, my experienc

  • Why not Quantum DX-30 (Score:5, Informative)

    by harmless_mammal ( 543804 ) <jrzagar&yahoo,com> on Thursday April 24, 2003 @02:35PM (#5802252)
    Instead of building a giant kluge, why didn't they buy a few Quantum DX-30s? Each one only takes up 4U, holds 20 drives, and the internal software emulates a tape library so it easily integrates with enterprise backup software from Legato or Veritas. If your environment requires off-site storage, you could attach a tape library to clone the backups and then store the tapes off-site.
    • Because I would be willing to bet that Quantum will charge a hell of a lot more per TB then this system cost (69TB for less than half a million is a bargain).
  • There is no way I would want to support that monster. I didn't see any mention of what happens when a drive fails. It's cake with most any SCSI Raid controllers. Look for the orange light, change the disk. Even promise makes IDE enclosures that do the same. With this system, do you have to take down the node when a drive fails? Sure it's a ton of space, but I'd give up some of the space for some easier administration. It only costs $70 per promise enclosure. That'll add about $12,000. So what. when
    • It mentioned it several times spread pretty evenly through the article. The 3Ware controllers switch in the hot backup and that specific drive is replaced. It doesn't directly say but it sounds like the defective drive could be hot-swapped, perhaps a function of the controller? In addition from the rest of the article it would be no problem to take down a single node for the short few minutes to switch out the drive.
    • 3Ware controllers support hotswap and hotspare, so on failure the data is recreated to the spare so need to rush in replacing the drive (in other words get around to it whenever you have time that week) and then you just unplug the drive and plop in a new one. Plus they have lost a total of 3 drives in the first year, I had to change out tapes every 2 weeks, this is a lot less work =)
  • I've been looking into backup to disk lately. We do about 600 Gig a week onto LTO tapes, 500 Gig of full and 100 of incrementals across all systems.

    My preference would be two sets of 4x160 in a RAID 5, using two Adaptec 2400 ATA RAID cards. That'd give me a formatted capacity of 2x 409 gigs. I'd want two of those systems available so I could have two fulls and two sets of incrementals on hand at any one time.

    The only stumbling blocks I've found are: finding a 2 or 3U box that will accept two of the 24
  • The point is, what is the worst case disaster that can happen on site? If the site itself is sufficiently secure, there may be little point in having off-site storage for relatively shortlived data. It's pretty difficult to steal one of these systems, and if it is in a tornado-proof basement suitably protected from flooding, anything that takes out both it and all the surrounding systems with the live data is also likely to take out the need for the data. It's clear that this is transient stuff - not like f

  • Bad idea. (Score:4, Funny)

    by Znonymous Coward ( 615009 ) on Thursday April 24, 2003 @02:44PM (#5802359) Journal
    A hard drive is sensitive to vibrations and has too many moving parts. The only reliable backup media is punch cards. Just don't store them near liquids.

  • Three Words: (Score:3, Informative)

    by Null_Packet ( 15946 ) <nullpacket@@@doscher...net> on Thursday April 24, 2003 @02:47PM (#5802397)
    Spinning Disk Backups

    It's being done all over. Some people are using Network Appliances, some people are using Linux machines. Even Legato, a major player in the backup market supports backup 'staging' to spinning disk to decrease backup windows.

  • Tape vs disk backups (Score:2, Insightful)

    by mikefocke ( 64233 )
    If you backup to disk, do you have the legal records you are required to keep?

    I've been saved several times by being able to retrieve files 5 years old that the lawyers wanted. Because I had multiple layers of backup, even though I deleted the files from my system 3 years ago, I was able to retrieve the files from tape. They were worth far more to the lawyers than the cost of the whole backup system and tapes could ever have cost.

    The typical disk backup setup does not support such archiving in depth. And
  • Somewhere I read "The sum of human knowledge is stored on magnetic media with a one year limited warranty"

  • tape's still bigger (Score:3, Funny)

    by raduga ( 216742 ) on Thursday April 24, 2003 @02:53PM (#5802468)
    Let's see...

    576 x 160GB
    = 92 terabytes
    = .092 petabytes
    = .00009 exabytes
    So... my vintage EXB-8200 beats your puny RAID by a factor of more than ten thousand.
  • StorageTek offers an IDE-based SAN storage device (BladeStore) that exceeds this and would be a whole lot easier to manage.

  • We have a unique backup method that is solid-state and faster than tapes.

    What we do is plug a digital camera into the server, and copy everything to its flash media card inside. When we go on vacation we just take the backup "off-site" to the Bahamas.

    And in the event of failure we also have a 256MB backup of the first bit of stuff on the hard drive, and a picture of the server room so we know what to order after it melts in a fire.

  • Let's see... (Score:3, Insightful)

    by stienman ( 51024 ) <`moc.scisabu' `ta' `sivada'> on Thursday April 24, 2003 @03:11PM (#5802660) Homepage Journal
    576 Hard drives.

    Assume 5 years MTBF.

    That end up being 100 Hard drive failures per year, about $10,000/yr, not counting labor.

    Or 2 per week. ($200/wk), if efficient to replace then add another $100/wk for ordering, shipping, storage, replacement and disposal.

    That's assuming good cooling and low usage (equivilant to an intermittant home user - which is what I expect a good backup system to get used to)

    So, ignoring the cost of the initial investment, they'll be paying up to $15,000 per year to maintain this backup solution.

    This is more expensive than many traditional backup methods, such as tape.

    However there were a few 'gimmes'. Firstly, the array only has to last 5 years. Secondly they are using 5400rpm hard drives - much cooler. Thirdly, these hard drives have a 3 year warranty, which is better than most places will give you now.

    So it's likely that the maintenance cost, in this case, is going to be low compared to the initial investment.

    The real problem, then, is the tendancy to keep an old system long past its prime and original intent. Someone in the future will say, "Instead of junking the system and upgrading to new technology, let's just throw larger hard drives in there each time one fails and up the capacity. Eventually it will cost $10k or more per year, and they won't know it.

    -Adam

  • Optical tape? (Score:3, Informative)

    by gweihir ( 88907 ) on Thursday April 24, 2003 @03:26PM (#5802876)
    For some years there have been rumours of optical tapes with capacities in the several hundreds of GB or even several TB per cartridge, but no products that I am aware of so far.

    Still I think that this misbalance between tape prices and HDD prices cannot last.

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