Hard Drives Instead of Tapes? 484
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."
Sound fine, but... (Score:2, Insightful)
I mean, sure tape isn't great, but it's a lot more transportable than harddrives.
I don't know if that is a good idea (Score:4, Insightful)
This would work for limited installations (Score:3, Insightful)
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...
Offsite? (Score:5, Insightful)
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.
Help me understand... (Score:5, Insightful)
sPh
ack! (Score:5, Insightful)
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
Re:Offsite? (Score:3, Insightful)
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 automated, and I never have to worry about swapping out tapes or having one streach on me, and it was far cheaper than the equivelent tape based system.
Re:I don't know if that is a good idea (Score:4, Insightful)
The best backup solution would be a bunker with hard drives, backed up via fiber in real time.
Re:Tape will be with us for a while yet... (Score:4, Insightful)
I wouldn't want to support it... (Score:2, Insightful)
Re:Sound fine, but... (Score:3, Insightful)
Re:Compliance (Score:5, Insightful)
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.
Re:Tape technology not keeping pace... (Score:5, Insightful)
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.
Re:Compliance (Score:2, Insightful)
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.
Tape vs disk backups (Score:2, Insightful)
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 disks do not like to be stored without being used so trying to read a disk that was written 2 years ago is very problematic if it hasn't been rotated and kept warm and free from condensation that plays havoc with bearings.
We use disk backups for nightly and weekly backups to allow quick restores from the aw shucks events that do occur but we also back up everything to tape and archive it off site.
Off Site Backup +/- (Score:4, Insightful)
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.Re:Far more practical (Score:5, Insightful)
Let's see... (Score:3, Insightful)
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
Re:Sound fine, but... (Score:4, Insightful)
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.
Re:Why not Quantum DX-30 (Score:3, Insightful)
Re:Help me understand... (Score:2, Insightful)
Of all the needs for backup, much is due to equipment failure. Not natural disasters.
Some of my backup needs, and probably the major issue at universities, is due to the stray loss or erroneous deletion of files. Not a tornado.
The closest thing to a natural disaster people will run into are fires. And another building is quite sufficient.
Furthermore, to transport media, even tape, 50 km away, you've got have that infrastructure or, in using public infrastructure such as USPS, UPS, FedEx, and other delivery services, you then have to worry about security and that means crypto. For some, their files are not worth the added hassle of delivery and receipt of media, repackaging, the cost, and the extra steps to physically and computationally secure their data.
You also have to consider purpose. For my computer backups, I keep all my backups on multiple media types (CDR and hard drives) in 2 firesafes (and water sealed) located in 2 areas of the building. The lower one is in the basement with cement blocks around it. In order to take that out, I'd be dead as well. There's no personal backup system for that (maybe in 50 years), and the data is of interest only really to myself, so it's survival is contigent and useless if I'm not around.
Re:Tape will be with us for a while yet... (Score:3, Insightful)
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 a spare. You then take out the bad drive and replace it. To protect data, you need to keeps the disks spinning, and that consumes power. With lots of drives, it's lots of power.
One vendor has a hybrid solution that has disks both online and offline emulating a tape library. When disks aren't in use, they spin down. You get the best of both worlds - fast access time and storage that doesn't require power all of the time. It's great for nearline restores, but isn't designed (pricewise) for long-term storage.
In an enterprise world, I see people use SCSI- or FCAL-based SAN/NAS storage with nearline recovery data on IDE farms and long-term archive storage on tape libraries. The software to manage the data can be complicated and/or expensive.
In a budget world, I see people use IDE storage for both active and nearline and archive storage. The only difference between the storage is that the disks on the nearline or archive storage are larger and are used less frequently.
If you have data that gets read frequently after it is backed up or which requires fast recovery times, use nearline disk. If you have data that needs to be archived without any immediate requirements to read it in the near future, use archive tape.
-ez
Re:Far more practical (Score:3, Insightful)
Re:Help me understand... (Score:3, Insightful)
Then you're probably out of business anyway, so what does it matter at that point?
Re:Far more practical (Score:3, Insightful)
OTOH, my father has 40-year-old punch cards that read just fine. (Course, that doesn't scale to terabytes.)
The upshot is that for long-term (>10 years) backup, have a refresh plan in place, where the data is periodically verified, and if necessary, extracted and copied to fresh media. (I have some 15-year-old files I did this to, moving them from QIC tape to CD-R. Nothing was wrong with the tape, but I only have one QIC drive, which could fail at any time.)
For my ultra critical data, I keep a backup of the backup locked in a bank vault.
What about hackers and screwups? (Score:1, Insightful)
I don't see off-site as a problem if you can afford a second unit hooked in with a high speed network. The problem I do see is hackers, and, well, administrator screw-ups. With all copies of your data on-line, if it should get accidentally or purposefully deleted, you're totally screwed. The only other issue is you're talking really large, you have a scaling limitation in power and weight.