Are Tape Backup systems obsolete?

Are Tape Backup systems obsolete?

Summary: In order for the Tape Backup system to become more economical, I calculated that it would require more than 56 Tapes to break even. That would be a massive 28 by 400 GB backup set which is massive even for large enterprises. Furthermore, Hard Drives are rapidly dropping in price and 300 GB Hard Drives are already in the sub $100 range.

TOPICS: Data Management

One of the most tedious and complex jobs in the world of IT is data backup.  Not only is it complex, but the use of mechanical Tape loaders make the system very prone to breakage and the Tapes themselves are not very durable and must be discarded on an annual or at least on a biannual basis.  Conventional IT wisdom has always dictated that Tape Backup is the only way to economically backup large amounts of data, but does this still hold true in the age of ultra-cheap hot-swappable Hard Drives?

Let's take a state-of-the-art Tape backup system like the HP Storageworks 1/8 Ultrium 960 Autoloader.  I chose this particular device because it represents one of the most cost effective Tape Backup solutions with very high performance and capacity at a relatively low price.  Each Ultrium 960 Tape has a true capacity of 400 Gigabytes and the HP Autoloader is capable of housing 8 Tapes at a time with a read/write throughput of 80 megabytes per second.  The lowest price I found for Ultrium 960 Tape was $68 per Tape and the HP Autoloader was $5000.

Now we look at what it would take to do the exact same thing using Serial ATA hot-swappable Hard Drives.  400 GB SATA Hard Drives cost $142 and it would probably cost an extra $800 for a server that could house all the extra drives internally compared to something that would act as the server for the Tape Backup Autoloader.  We won't count the SATA controllers because the Tape Backup system would need a fast SCSI controller anyways so it would be a wash in this respect.

If we tried to build two 8 by 400 GB backup sets which is 6.4 terabytes, the Tape Backup solution would come out to $6088 and the SATA Hard Drive based solution would be $2272.  If we didn't actually need that big a backup set, the Hard Drive based solution would be even more economical since the $5000 Autoloader isn't needed.  In order for the Tape Backup system to become more economical, I calculated that it would require more than 56 Tapes to break even.  That would be a massive 28 by 400 GB backup set which is massive even for large enterprises.  Furthermore, Hard Drives are rapidly dropping in price and 300 GB Hard Drives are already in the sub $100 range.  The other factor that comes in to play is that Hard Drives last 2 to 4 times longer because Tapes are suppose to be rotated ever year while most larger hard drives have a 5 year warrantee so it can be argued that even the media itself is cheaper since you don't have to replace them as often.

Furthermore, Hard Drive based solutions are MUCH faster than any Tape Backup solution.  Having 8 SATA Hard Drives can operate at the same time and have an aggregate throughput of about five times faster than a single Ultrium 960 Tape.  While an Autoloader can hold 8 Tapes, only one Tape can be read or written to at a time.  Autoloaders are also mechanically complex and they break down often and they're very difficult to manage.  Note that in order to fully saturate the capacity of 8 Hard Drives, you must have a 10 Gigabit Ethernet adapter on the server.  Fortunately the cost of these adapters have come down to around $1000 but you'll still need a 10 Gigabit capable switch to plug it in to.

The other HUGE factor is the fact that you don't need to "rewind" a Hard Drive since it is random access.  This actually permits the use of bit-level backup solutions that let you maintain a synchronized copy of a file system without copying the entire file.  Windows Server 2003 for example would also allow you to implement a single-point storage system where replicas of files are only stored once on a file system.  The combination of all these factors can increase backup and restore performance several times.

Most modern backup software will permit the use of Hard Drive based solutions.  Off-site storage services don't care if you hand them a container with a Tape or a Hard Drive.  The only issue with Hard Drives is that you must put them in a thick-padded shock absorbent container but with proper care they should last much longer than Tapes [Update: Reader Adunlap posted this link where to get the padded casing].  So are the days of the Tape out numbered?  Only time will tell and it takes a long time to change conventional wisdom.

Topic: Data Management

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  • Linux Server Hack #38

    This [i]Linux Server Hack[/i] is also applicable to Windows (assuming Cygwin and RSYNCx.exe for Windows are installed) and is a secure way to channel backups across hosts.

    [b]Linux Server Hack #38:[/b]

    [url=]Using rsynch over ssh[/url]

    Thanks George.
    D T Schmitz
    • Rsync over ssh

      aaaahhh bliss when you add cron to the equation. I must spend some time sorting it out to work on Windows for all my friends who have no backups
  • one important thing to note

    Tapes are a lot easier to move around and the impact of letting one fall is definately less.

    But if you're willing to put that aside, it's definately a great solution. Especially when you replicatie it to another location in the night.
    • Tapes are very sensitive to other factors

      Such as temperature and humidity. Shock can be solved with an inch or more of padding.
  • DIY is always cheaper

    If you paid IBM for those hard drives (as Company 'F' would do) - they would cost 10x and ONLY fit in an IBM frame (whose price would scare any normal person). And you would (of course) need their "special" TSM software. After all was said and done, the price would be a wash.
    Roger Ramjet
    • Why TSM

      We use TSM in our head office wnvironments for backing up pSeries, iSeries and xSeries (Intel) kit but by choice. It doesn't have to be that - we use CA BrightStor in our department stores which is much more cost effective in that environment - not only that - I'm now looking at migrating from DLT to USB externals in that envoronment - well I would if it wasn't for NT4!
    • Business Finance 101

      I assume you are referring to how a product costs more if a business purchases it, as opposed to the individual. I was wondering if you could explain why this happens?
      Our company recently started a program where it asks us pee-ons for ideas on how to cut operating costs. One of the questions brought up in our quarterly meeting was this very thing. A couple of examples given were for instance, how the company pays $2 for a pack of light bulbs that would cost you or me 88 cents at Walmart. Another example was a shop-vac that cost the company $500, but can purchased all day long at Lowe's for $150.
      As with most of our questions, management didn't give us a very clear answer, but they illuded to the idea that it has something to do with only having to pay the supplier once every 45 days, rather than every time they order something.
      Is there more to it than this? Is it really cost-effective to pay a 227% mark-up on supplies just for a 45 day grace period?
      • Buying through IBM

        IBM routinely charges WAY too much for everything. That $2000 hard drive is nothing! My personal favorite is $5000 for the front door to a P690 rack. That's JUST THE FRONT DOOR. The rear door is extra ($4000). The entire price for 1 rack (no computer) is $45k (the $2000 power cord is a good example too).

        They way most purchasing departments are organized, if you want to buy something you need to get 3 different quotes and fill out a bunch of paperwork - whereas ordering it from IBM just takes a single PO.
        Roger Ramjet
      • re: Business Finance 101

        we're not unlike you in this respect. our accountants give the same reply when asked. it has to do with the fact that we pay in terms (30 days, 45 days etc.) instead of cash (or dated check) and that it is delivered as opposed to having someone go out and purchase it. All in the paperwork (or making the books look good) i guess.
      • re: business finance 101

        I?m no expert on corporate purchasing, but here are a couple of other points you may want to consider related to what may seem to be supplier cost effectiveness (in ineffectiveness):
        1) ?Portfolio pricing? ? one particular vendor may offer a broad array of products, some of which are more expensive than if you were to buy them elsewhere, some are less. You have to be careful when you look at one example or item purchased in isolation. When you combine all the products that the company buys from the vendor, it is likely that they are getting a lower price on average. For instance, the shop vac you mention may cost $350 more than if you bought it at Lowe?s but the light fixtures are $600 less, so the company is getting a $250 break on the suite of products. The idea is to look at all the products you buy together.
        2) Simplicity ? by working with one vendor (or a few) for particular product, the company can get all the products in one place. While on any individual item it might be worth it to go to a different source, think about how much time that it would take for an employee to research all the cost and supplier options, drive around town to get the products, etc. The manpower costs would likely more than offset any savings you?d get.
        3) Cash control ? don?t underestimate the savings associated with paying your bills 30-60 days later than you get the goods. Sure on one particular thing it may not be that big, but put it in the context of all the purchases a company makes. It could be significant. Plus, simplifying through fewer suppliers (and billing transactions) reduces the requirements on accounting and therefore means fewer people needed to write and process checks.
    • Then that's your own fault

      BTW, those hard drives from EMC or IBM are identical. They just have a slightly different mounting kit.
      • Depends on what we are talking

        SATA Drives are SATA Drives, whether version I or II or what ever else is out there. With some of those SCSI Drives that IBM had, there was some extra electronics attached, atleast on the older SSA systems. The newer ones, T40/D40 series and newer look to be standard. Then you have the matter of the new Storage systems of IBM's. Who really knows anymore.

        Yeah yeah, IBM is proud of their name. They have to find a couple suckers to pay for all that R&D for those 30 thousand patents they filed.

        As far as Hard drives are concerned, atleast SATA are more PnP based that you don't have to arrange much to set them up as a Hot Swap. Case in point though, swapping out a Hard drive does take a bit more time than a tape, but recovery is much faster.

        I have been using an external Firewire drive for back up for some time. Sure the speed isn't up to par, but the drives last a good couple of years and don't take as much time for restores. With my Backup setup, I only use the external drives for long term storage, the local drives are used for short term. The backup server has a fiber trunk to the File server. Though this isn't a pure off-site solution, atleast the odds of two buildings going up on smoke are a little less likely.
  • Rotation

    Tape backups typically are incremental daily, full weekly and are kept for one month. In this schedule you are looking at over four copies of the data. Still, tape backup does seem to be going the way of 8 track tape decks in Cameros.
  • Under protected

    George's solution seems horribly vulnerable to me. An accident or deliberate sabotage in one location and the company is toast.

    Not good.

    Of course I work in a truly paranoid environment. :) Our backup solution is quite involved. We take a full daily backup every day, 7 days a week, we rotate tapes on a lunar month schedule (meaning 28 full backups/month), tapes not in use on site are stored in a massive concrete and steel safe that's both fireproof and damn near bomb proof.

    In addition we use a snap server as a quick backup/restore mechanism, *and* we have an offsite hot-backup solution refreshed every two hours for critical data and daily with all data. And that server also has a lunar month full backup cycle.

    Did I mention both servers are raid 5 in the first place? :)

    Of course even with these precautions it's theoretically possible the company's data system could be taken out, say by an asteroid strike...

    But hey, at least I'm *trying*. (laughing)
    • I disagree

      The solution, when implemented properly, is simple, cost effective, and just a cheaper way of doing things.
    • Were are not as bad..

      but I do a semi-full backup every night that I keep for about a week. Then I do a full backup every weekend. And once a month I do a month end backup that gets saved. Right now I can go all the way back to 1997. I keep a set of the weekend backups at home and take the previous nightly backup home with me every day.

      The one thing we are missing is the off-site hot backup. Everyone we looked at was cheap to setup, but if you needed to retrieve anything you best be prepared to take it in the backside.
      Patrick Jones
      • home storage

        I don't know your business situation - but home storage of backups is one of the worst things I've seen while reviewing backups and BCP. A home is probably one of the least secure (fire, theft, water damage, etc.) locations for data storage.

        I remember working with a client that took his tapes home - but admitted that he just left them in the trunk of his car.
        • However..

          the probablility of my home and the office being destroyed at the same time is very low. If they are, then all hell has broken loose and the backups are not going to be needed :)
          Patrick Jones
          • more than just disaster recovery

            It's not always about disaster recovery, it's a question of whether your data is secured, but readily accessible if things go bump in the night. Again, I don't know your business, but how do you think a legal dept. would feel about about an admin taking home confidential HR information and storing it in a shoebox in the closet?(I've seen this before). And if you are a 24/7 shop, does that mean other admins have the key to your home to retrieve backups if they need them? What happens to the tapes when you get sick, go on vacation, or get hit by bus?

            For a small business - where you are "the guy", home storage can be acceptable if properly managed and secured. But I've seen it way too often in major coorporations.
          • And..

            offsite storage is better for protection? Who's to say someone at the facility isn't sneaking into your information. And online storage is no better. At least with tapes, I know I have them protected and no hacker will be able to sit at home and get to the data on them. Any medium in the wrong hands, can be retrieved with the right equipment. I would rather have tapes than hard drives in that situation. Mainly because there is the PITA factor with tapes.

            And the current set I keep at home is mainly just for disaster recovery. Otherwise, there are plently of "undeletes" that work well. Every once in a while, we do get a strange situation where the file needs to come from a specific tape, but usually any one of the last 5 days will work. The month end tapes are more for convenince. Only the previous years worth is in a fire proof safe.
            Patrick Jones