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Will this work for a backup solution?

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October 13, 2008 6:15:23 PM

Hello!

I am trying to implement a backup/recovery plan for our small organization, which will backup about 100gb per night 5 nights a week.

I would like to do the following:

* Attach a NAS drive like this one: http://www.newegg.com/Product/Produc...82E16822186025 to our ethernet switch
* Unit has 4 500gb drives
* configure them in 2 sets of 2 drives; mirrored RAID 1
* Each one will hold appox. 1 week of our backups
* So we backup for 2 weeks
* take the first set of two drives out for safe storage
* back up again for 2 weeks on remaining set
* after 2 weeks, swap sets


Will this work? can RAID 1 or 0+1 be configured this way?

If not, Please offer any suggestions that may.

All help greatly appreciated!

Thanks,
m

More about : work backup solution

October 13, 2008 9:16:24 PM

RAID units are for redundancy/availability/uptime, not for backup.

Using a swappable non-RAID external drive is what you're looking for.
October 14, 2008 1:51:27 PM

I am thinking about a similar setup. I know RAID units are not for backup and I would not use them in normal operation for this reason, but using a RAID setup as saint m described cuts backup time in half since one backup operation results in two identical backup drives instead of having to do two separate backups. This is the 'redundancy' part of RAID. What other reason could there be for not doing it this way? It would seem to be a huge time saver.
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October 14, 2008 2:11:15 PM

Sadly it is still cheaper, and easier to go with the old Tape drives, or if you must, backup on a large external drive. (I'd still use the tapes)

example: http://www.newegg.com/Product/Product.aspx?Item=N82E168...

Tapes: http://www.newegg.com/Product/Product.aspx?Item=N82E168...

Do 1 full backup per week, followed by nightly incrementals (inc's pull any changes since the last full)

Using a RAID defeats the purpose of backups (RAID should never be used for backups, as each time you remove a disk, you "break" the array).
October 14, 2008 3:43:07 PM

Cost isn't as major a factor as protecting our data is, and tapes are very slow (sequential access) and less reliable than hard drives, so I think my days of tape backups are long gone. You say removing drives from a RAID system breaks the array....OK, that may be a good reason not to use this method. Is this the only reason and is it a big problem as long as the drives are reinserted in the same order?

The idea of using RAID for this setup is just to get the second automatic backup, so (other than breaking the array), why should it 'never' be used for backups?
October 14, 2008 4:01:01 PM

russff said:
Cost isn't as major a factor as protecting our data is, and tapes are very slow (sequential access) and less reliable than hard drives, so I think my days of tape backups are long gone. You say removing drives from a RAID system breaks the array....OK, that may be a good reason not to use this method. Is this the only reason and is it a big problem as long as the drives are reinserted in the same order?

The idea of using RAID for this setup is just to get the second automatic backup, so (other than breaking the array), why should it 'never' be used for backups?


Heya,

RAID1 (mirroring) is fantastic for backups. You're getting two backups for redundancy. Nothing wrong with going this route. It's no more risky than any external or any other backup scheme. The simple way to look at it is that no system is capable of being 100% reliable for your backups over time. The only way to make your success of never losing data is to have multiple copies of it separately. Mirroring is exactly that. The more mirrors you have, the more odds you'll never lose anything. Ie, never put your eggs in one basket.

You could easily build something like this on your own, or buy a pre-made sollution. Overall, you'll get way more bang on your buck in a self-built system. Just grab a nice big tower, fill it with some drives, and mirror away. Toss in your 10/100/1000 NIC and back up to your whim. You can build a several terabyte solution (single system) for less than $800 ($200 system allowance, +/- 3TB storage, broken up however you want to achieve several mirrors). And yes, you could easily backup to several 500gig drives and take them out and swap back and forth. However, the more you take them in and out and re-use the RAID, the more odds you'll get a head thrash or other longevity related death to your drive's data or the drive itself. Swapping hardware over and over can hurt you. Instead of doing the big swapping thing, here's another suggestion:

Build two systems, independent of each other. Each with a set of mirrored 500gig drives, or go higher with 750gig (cost per gig is getting great!). When one is full, start backing up to the other. When it gets full, switch back to the other. This way you're never physically changing your hardware or plugging/unplugging and powering down, etc (the more power on/off your disks do, the less long their life span is). They can just sit back, idle at low power, and be used when you need them. The only other thing to do is to make sure they're on good power protection units to ensure a black/brown out doesn't cut you off while they're writing (hope you planned for that!).

Example hardware:

Motherboard: http://www.newegg.com/Product/Product.aspx?Item=N82E16813131342 $55 (buy two) (Asus, RAID1, 10/100/1000 lan included, video included, 4x sata ports). Buy two.

CPU: http://www.newegg.com/Product/Product.aspx?Item=N82E16819103256 $60 (buy two) (AMDx2 4450e, dualcore, includes fan/heatsink). Buy two.

Memory: http://www.newegg.com/Product/Product.aspx?Item=N82E16820231098 $38 Gskill, 2gigs. Only buy this once, and put 1gig of ram on each motherboard.

Harddisks: http://www.newegg.com/Product/Product.aspx?Item=N82E16822136150 $95 each. Get 4~6. Instead of going 500gig, get 750gigs so you have room to spare in case your data goes up for any reason. These are low power ones, so you can idle and save costs on energy.

Lastly, just get two cases and two PSU's that are decent. Throw them on your network. Do your business. Each system using the above scheme is only $325 each (mobo/cpu/1ramstick/2hd's), then add case/psu (~$100~150, because you want a good PSU) and you have two systems capable of what you want for about $500 each. Make sure you have good power protection/batteries, and you're set.

Very best,
October 14, 2008 4:48:53 PM

If cost is not a concern, consider an Off-Site Solution.
Then you could FTP up your data every night.

If you data is so important, how bad would it be to lose a weeks worth of data in a theft/fire, etc.....

You could always then pull the data back down after a week or two for longer term storage on a HDD.
October 14, 2008 4:53:54 PM

Thanks for the suggestion. So constantly removing/installing drives in a RAID 1 system is NOT a real problem (as far as 'breaking' the RAID goes)? The only other issue with your suggestion is the systems are not portable, there is no way to remove a drive offsite without toting the entire tower. My thought was to get a premade NAS RAID system (example D-Link DNS-323) and just drop it on the network, this way the entire unit can easily be removed offsite.
October 14, 2008 5:04:15 PM

russff said:
Thanks for the suggestion. So constantly removing/installing drives in a RAID 1 system is NOT a real problem (as far as 'breaking' the RAID goes)? The only other issue with your suggestion is the systems are not portable, there is no way to remove a drive offsite without toting the entire tower. My thought was to get a premade NAS RAID system (example D-Link DNS-323) and just drop it on the network, this way the entire unit can easily be removed offsite.


In that case, look into a small eSATA 2~4 disk external RAID server box. Essentially it's a powered box that is big enough to hold around 4 hard disks. They are sometimes hot swappable, sometimes not. They hook into the box, and on the back is an eSATA port so you can plug into any computer that has an eSATA connection (ie, external SATA). So any computer can then serve as your machine for accessing the network and allowing you to use your "NAS" essentially.

Very best,
October 14, 2008 5:37:32 PM

Will it work? Yes.
Is it a good solution? Not really.

Most of the capabilities YOU'RE looking for in a raid system are handled better by using distributed file systems. Check that out first.

Second, you might wonder why so many of us have changed over to virtual servers on virtual storage with virtual apps when we can. Kinda hard to break when there's redundant machines spread geographically, ya know?

Back to you're issue......
Put one of the replica servers offsite and pump data to it in one of two ways. (instant business continuity for cost of backup system)
1. constant packet stream
2. bury the wire with traffic overnight.
October 15, 2008 2:28:22 PM

russff said:
I know RAID units are not for backup and I would not use them in normal operation for this reason, but using a RAID setup as saint m described cuts backup time in half since one backup operation results in two identical backup drives instead of having to do two separate backups.


RAID would not cut the backup time at all. The data is still a fixed size, and takes a fixed amount of time to write to the backup device, no matter what. It doesn't matter if the backup device is a RAID 1 making 2 simultaneous copies or not, that's still no faster than a single drive.

russff said:
Cost isn't as major a factor as protecting our data is, and tapes are very slow (sequential access) and less reliable than hard drives, so I think my days of tape backups are long gone. You say removing drives from a RAID system breaks the array....OK, that may be a good reason not to use this method. Is this the only reason and is it a big problem as long as the drives are reinserted in the same order?

The idea of using RAID for this setup is just to get the second automatic backup, so (other than breaking the array), why should it 'never' be used for backups?


First, modern tape drives are very fast. LTO-3 can do 80 MB/sec, which is faster than most hard drives. LTO-4 can do 120MB/sec. Tape is, and has always been, the most reliable backup method there is. You can take LTO tapes and drop them fully submerged into muddy water, and a data recovery company can still recover 100% of your data. Try that with a hard drive.

Tape has the big advantage that you can rotate tapes, and the system is designed for this. Forget holding 2 backups. Hold 20 backups of past days/weeks/months if you want. Permanently archive old data to tape and stick it on the shelf. No hard drive/RAID backup system can do that.

It's easy to take tapes off site. They're small and durable. You can't reliably transport hard drives off site and back all the time. The constant vibration and shocks will cause them to fail prematurely.

russff said:
Thanks for the suggestion. So constantly removing/installing drives in a RAID 1 system is NOT a real problem (as far as 'breaking' the RAID goes)?


Yes is IS a real problem. You're staking the integrity of the backup system on the rebuild code of a consumer-grade RAID box. Browse this forum real quick and see how many threads you can find that read like this:

Umm... my external NAS tower dropped off line last night, and when I replaced the faulty drive it wouldn't rebuild. How do I get to my data?

If "Cost isn't as major a factor as protecting our data is" then a backup solution based on consumer crapola is absolutely out of the question.

Check out these LTO drives from HP. These may work great for you, depending on how much data you need to back up. (1 LTO-3 tape = 400GB native). The have LTO-3 drives as low as $1849 from HP ($1779 from CDW), and LTO-4 from $3799 ($3663 at CDW).

If you want more automation, check out the 8-slot LTO-4 autoloader at $5174.

I have the 24-slot LTO-4 version of this tape autoloader, running it with Backup Exec 11d. I back up 1 TB of data every month, differentials in between (every day), and I back up 4 TB of data every 90 days from a media library. The thing works flawlessly.

Now, mford makes a good point that if you've deployed a virtual machine architecture like VMware, that there are other backup solutions that are available. However, most small businesses have not virtualized things yet, and I'm assuming you fall into this category.
October 20, 2008 7:39:51 PM

Thanks for all the responses and info. Right now I am leaning away from RAID and to a swappable drive bay of 1 to 1.5 gig drives, sorta like this one:

http://www.startech.com/item/HSB320SATBK-3-Drive-Tray-L...

I figure I can store one away when it's full and swap in another one.

My question now is about configuring the backup software to go from one drive bay to another when the first drive is full. Having never done this before I'm not sure if that is a problem.

Any more thoughts? Sorry for the delayed followup, stuff happens ;-)

Thanks,

m
October 20, 2008 7:54:10 PM

Quote:
mford66215

Most of the capabilities YOU'RE looking for in a raid system are handled better by using distributed file systems. Check that out first.


At the risk of sounding dumb, I'm not sure what you mean by distributed file systems in this context. Can you give me an example?

Thanks for any info,

m
!