#174711 - 11/08/2003 13:38
DVD-RAM as a replacement for DAT
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carpal tunnel
Registered: 30/10/2000
Posts: 4931
Loc: New Jersey, USA
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I am going to build a new server for our small office soon (12 people). Currently, we are running an NT 4.0 server I built 6 or 7 years ago and upgraded 1.5 years ago. We are still using 2.0GB DAT tapes for backup and it is a pain in the ass. Recently, the drive went dead and I had to find a replacement that would work with our antique ARCserveIT software and be backward compatible with our DDS-1 tapes.
We backup every day, so we have 31 daily tapes that get written-over evey month and then we keep 12 end of month tapes per year. We are pretty comfortable fitting our data onto the 2GB tapes, but more headroom would be nice. Plus, the tapes break pretty often with the new Seagate drive I put in.
I was wondering if there is a simple/cheap software package capable of doing scheduled backups onto a DVD RAM drive. I am interested in DVD RAM because it would more than double our backup capacity and the plastic shell makes me think it's durable as we would use most of them over and over again. The ability to mount the media like any other DVD/CD is a plus compared to tape as well. We would likely be moving to Win 2000 Advanced Server or 2003 Server so NT 4.0 sopport is not necessary. So, does anyone have experience with this? Thanks! 
Edited by robricc (11/08/2003 14:00)
_________________________
-Rob Riccardelli
80GB 16MB MK2 090000736
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#174712 - 11/08/2003 13:43
Re: DVD-RAM as a replacement for DAT
[Re: robricc]
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carpal tunnel
Registered: 20/12/1999
Posts: 31600
Loc: Seattle, WA
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I have nothing but bad things to say about DAT as a backup medium. For us, they never worked reliably and were always a pain in the ass.
IMHO, DVD-RAM is not yet proven as a reliable and easy backup medium. If you want reliable and easy, you want DLT. Period.
When we switched from DAT to DLT, suddenly life became easy. The drives and tapes are indestructible and rock-solid reliable. Everything just works, I never get tape errors. With DAT, I had to have the thing re-scan the tapes to verify everything was correctly backed up. Which of course meant that much more wear and tear on the tapes and the drives. With DLT, I've gotten to the point where it trust it well enough that I don't even need to do a re-scan.
Seriously consider DLT instead of DVD.
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#174713 - 11/08/2003 13:47
Re: DVD-RAM as a replacement for DAT
[Re: tfabris]
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carpal tunnel
Registered: 30/10/2000
Posts: 4931
Loc: New Jersey, USA
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I will look at DLT. I haven't looked at it yet because my impression is that it's extremely expensive. I will keep it in mind though.
Can you suggest any backup software for a (very) small business? All we need to do is schedule a backup to be run everyday and pop the media out of the drive when done.
_________________________
-Rob Riccardelli
80GB 16MB MK2 090000736
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#174714 - 11/08/2003 13:53
Re: DVD-RAM as a replacement for DAT
[Re: robricc]
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carpal tunnel
Registered: 20/12/1999
Posts: 31600
Loc: Seattle, WA
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I will look at DLT. I haven't looked at it yet because my impression is that it's extremely expensive. I will keep it in mind though. It used to be. But now SuperDLT is out and the older DLT technology (which is lower capacity but still rock-solid reliable) has come down in price. Not sure if it's come down enough for you or not. But think about how much time you've been spending fuc king around with problems with the DAT tapes and add it all up. How much money is that time worth to you? Now imagine sticking a tape in every night and forgetting about it. That's DLT.
Can you suggest any backup software for a (very) small business? All we need to do is schedule a backup to be run everyday and pop the media out of the drive when done. If you don't want to spend any money, then there's backup software built-in to most versions of Windows which will do it for you. And keep in mind that most of the time when you buy a backup drive, it will come with software.
Personally, I swear by ArcServe, but it's so feature-heavy that even setting up a simple "stick one tape in each night" backup system is a bit of a learning curve. It might be overkill for what you're looking for. Then again, you're a pretty tech-savvy guy so I don't think ArcServe would be daunting to you at all, and you'd eventually grow into its more powerful features.
Hmm. I think some of the DLT drives are sold with ArcServe included....
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#174715 - 11/08/2003 13:53
Re: DVD-RAM as a replacement for DAT
[Re: tfabris]
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carpal tunnel
Registered: 08/03/2000
Posts: 12341
Loc: Sterling, VA
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You don't think DVDRAM will be fine for the amount he's backing up? I mean, the primary advantage that tape has as a backup medium is its size. The amount of data he has to backup is relatively small (my father's office just installed some monster-sized tape backups which they need primarily for all the space that's used by the desktop publishing division).
The advantage to DVDRAM, in my mind, would be far faster recording speed (faster than all other writable DVDs, I believe). You'd also have much faster seek times if you needed to replace data.
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Matt
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#174716 - 11/08/2003 13:54
Re: DVD-RAM as a replacement for DAT
[Re: tfabris]
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carpal tunnel
Registered: 30/10/2000
Posts: 4931
Loc: New Jersey, USA
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After looking on pricegrabber quickly, it seems this is the cheapest DLT drive. That is on the border of being too expensive. However, the $31 per tape puts it way out of affordability.
I can understand the need of quality and reliability, but the people that pay the Amex bill don't.
_________________________
-Rob Riccardelli
80GB 16MB MK2 090000736
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#174717 - 11/08/2003 13:55
Re: DVD-RAM as a replacement for DAT
[Re: Dignan]
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carpal tunnel
Registered: 20/12/1999
Posts: 31600
Loc: Seattle, WA
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You don't think DVDRAM will be fine for the amount he's backing up? You're assuming that capacity is the only factor.
We're talking about someone who's just lived through the hell of DAT backup, and right now I think that reliability and ease of use are at the top of his priority list. Any backup medium will have the capacity he needs, so it's the other features of the system that will be most important.
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#174718 - 11/08/2003 13:57
Re: DVD-RAM as a replacement for DAT
[Re: robricc]
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carpal tunnel
Registered: 20/12/1999
Posts: 31600
Loc: Seattle, WA
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That is on the border of being too expensive. However, the $31 per tape puts it way out of affordability.  That's too expensive?
You're not understanding. These tapes are indestructible. You can re-use them so many times it's not even funny. Unlike the DAT tapes which wear out if you look at them sideways.
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#174719 - 11/08/2003 13:59
Re: DVD-RAM as a replacement for DAT
[Re: tfabris]
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carpal tunnel
Registered: 30/10/2000
Posts: 4931
Loc: New Jersey, USA
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I mis-typed in my original message. We are running ARCserveIT 6.61 on our NT box currently. It is reasonably easy to handle, but I don't know kind of junk they threw into any newer version that may be overkill. I am sure it is not exactly cheap.
I have experience with the backup built into 2000 and XP and I thought it was pretty good. So, you would trust that software to properly do a daily backup?
_________________________
-Rob Riccardelli
80GB 16MB MK2 090000736
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#174720 - 11/08/2003 14:00
Re: DVD-RAM as a replacement for DAT
[Re: robricc]
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carpal tunnel
Registered: 20/12/1999
Posts: 31600
Loc: Seattle, WA
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I have experience with the backup built into 2000 and XP and I thought it was pretty good. So, you would trust that software to properly do a daily backup? Never used it, I just know that it's there. If you're already using ArcServe 6.x, then you're fine, I'd stick with that.
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#174721 - 11/08/2003 14:04
Re: DVD-RAM as a replacement for DAT
[Re: tfabris]
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carpal tunnel
Registered: 30/10/2000
Posts: 4931
Loc: New Jersey, USA
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Maybe it isn't. It really depends on how re-usable they are. Every week, we have about 2 DAT tapes break in the drive ($2-3 per tape).
How many times can you write to a DLT? If you say more than 104 times (two years worth for us), it may be worth it.
_________________________
-Rob Riccardelli
80GB 16MB MK2 090000736
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#174722 - 11/08/2003 14:09
Re: DVD-RAM as a replacement for DAT
[Re: robricc]
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carpal tunnel
Registered: 20/12/1999
Posts: 31600
Loc: Seattle, WA
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How many times can you write to a DLT? If you say more than 104 times (two years worth for us), it may be worth it. Easily.
You could, with the kind of capacities you're talking about, append multiple backup sessions onto the same tape instead of overwriting each time, extending the life of the tape even more. As well as reducing the number of times per week that you need to change tapes.
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#174723 - 11/08/2003 14:15
Re: DVD-RAM as a replacement for DAT
[Re: tfabris]
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carpal tunnel
Registered: 30/10/2000
Posts: 4931
Loc: New Jersey, USA
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...append multiple backup sessions onto the same tape instead of overwriting each time... But then, if the tape breaks on Friday and we already have Monday-Thursday on there and the server also happens to blow-up we're screwed.
I will have to investigate more into DLT. An initial hit of $1600 for drive and tapes is going to be a tough thing to explain.
_________________________
-Rob Riccardelli
80GB 16MB MK2 090000736
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#174724 - 11/08/2003 14:25
Re: DVD-RAM as a replacement for DAT
[Re: robricc]
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carpal tunnel
Registered: 25/12/2000
Posts: 16706
Loc: Raleigh, NC US
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You can get a DLT 4000 drive for as low as $400 according to a quick search on PriceWatch. That'll hold 40GB with hardware compression. I imagine the tapes are cheaper, too.
_________________________
Bitt Faulk
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#174725 - 11/08/2003 14:52
Re: DVD-RAM as a replacement for DAT
[Re: robricc]
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pooh-bah
Registered: 20/01/2002
Posts: 2085
Loc: New Orleans, LA
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So buy 10 tapes, label them M-F plus 3 for EOM, and just set the script to append to tape every week, resetting only on the first week of the month. The odds of both the EOM tape and a failing tape being on monday the first are pretty slim. So now, rather than 40+rtapes, you need 15 or so. Whatever you need yo be comfortable.
In other words, ditto on the DLT. We were using DDS3 and just switched to a DLT Library using amanda as the client. We change the tapes once a month. DDS broke way too often to be considered reliable.
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#174726 - 11/08/2003 15:08
Re: DVD-RAM as a replacement for DAT
[Re: robricc]
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carpal tunnel
Registered: 08/06/1999
Posts: 7868
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As everyone else has basicially said, go DLT. Since I assume Ultrium is out of your price range...
Biggest reliability reason why DLT is better is that the data part of the tape never touches anything beyond the other parts of the tape while wound around the spool. Even the recording head dosen't make direct contact, it hovers. Thus heads last much longer, and there isn't a few rollers inside the tape drive contacting the data part of the tape.
For those wondering what Ultrium is, it's basicially a slightly better DLT technology. Same single spool idea, but a much improved pickup method (avoiding the DLT problem of dropped leaders), and a data chip inside the tape that stores the table of contents, allowing a much faster seek time. Native capacity of Ultrium is currently at 200gb uncompressed.
Price wise, you might look into DLT VS80 drives. These use the same DLT IV tapes that other 40/80 GB DLT drives use, but they store data on them in a method that allows the drive to be cheeper, as it dosen't move the head around.
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#174727 - 11/08/2003 15:16
Re: DVD-RAM as a replacement for DAT
[Re: drakino]
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carpal tunnel
Registered: 20/12/1999
Posts: 31600
Loc: Seattle, WA
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Same single spool idea, but a much improved pickup method (avoiding the DLT problem of dropped leaders) Heh, our original DLT drive got a disconnected leader after a few years of use, and I went back and forth with their tech support a few times before I got one of the more educated drones who recognized it for what it was and said, "OH! Just open the drive with a screwdriver and re-hook the loose leader."
And don't let that scare you off about the reliability of the drives, Rob. From what I understand, the loose leader problem is one of the most common failures of a DLT drive, and ours ran flawlessly for years prior and years after that incident. It was the only incident we had with that drive. In other words, even the most common failure mode has an MTBF measured in years, and is easily fixable in a couple of minutes.
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#174728 - 11/08/2003 15:24
Re: DVD-RAM as a replacement for DAT
[Re: robricc]
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carpal tunnel
Registered: 20/12/1999
Posts: 31600
Loc: Seattle, WA
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But then, if the tape breaks on Friday and we already have Monday-Thursday on there and the server also happens to blow-up we're screwed. True, but in my experience, our DLT drives and tapes are more reliable than the servers they're protecting.
But, yes, as was suggested, a rotated grandfathering system with appended sessions would allow you to use fewer tapes without sacrificing the data's security.
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#174729 - 11/08/2003 15:31
Re: DVD-RAM as a replacement for DAT
[Re: tfabris]
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carpal tunnel
Registered: 08/03/2000
Posts: 12341
Loc: Sterling, VA
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No, I understood your point. Reliability is important, I'm sure, but it just seems like overkill. Why pay that much for a tape backup system that runs 40GB tapes when he doesn't need nearly that much?
Don't get me wrong, if he wants sheer reliability, I yours is the way to go.
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Matt
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#174730 - 11/08/2003 15:36
Re: DVD-RAM as a replacement for DAT
[Re: Dignan]
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carpal tunnel
Registered: 20/12/1999
Posts: 31600
Loc: Seattle, WA
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Why pay that much for a tape backup system that runs 40GB tapes when he doesn't need nearly that much? In my experience, the amount of data needing to be backed up will increase exponentially as time goes on. Investing in that kind of headroom is not illogical.
Besides, like we were saying, you can append to tapes. So if he's only backing up 2gb, then one tape can contain 20 full backups.
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#174731 - 11/08/2003 15:38
Re: DVD-RAM as a replacement for DAT
[Re: tfabris]
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carpal tunnel
Registered: 08/06/1999
Posts: 7868
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And don't let that scare you off about the reliability of the drives, Rob. From what I understand, the loose leader problem is one of the most common failures of a DLT drive, Yep. Out of all our tech support calls, this is common. Quantum based DLT drives (almost all of them) will flash all the LEDs on the right hand side. As Tony said, it's easy to fix, and is rare to happen to a drive. Most common cause of it is a bad tape being inserted. Most cases, a tape goes bad if it gets dropped from a few feet. We have a 4 step tape verification procedure for DLTs:
1. Shake the tape gently. There should be no noise from the tape, as all components should be secure.
2. Push in the spool wheel on the bottom a bit, and release. It should spring back into place following your finger.
3. Open the top of the tape and ensure the tape leader is visible in the opening. It looks like a rounded section of the end of a tape, and contains a hole.
4. Ensure that hole on the tape is not broken.
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#174732 - 11/08/2003 15:39
Re: DVD-RAM as a replacement for DAT
[Re: tfabris]
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carpal tunnel
Registered: 08/03/2000
Posts: 12341
Loc: Sterling, VA
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True. And besides, these tape machines are much faster these days. The most recent ones that were installed in the office are very fast. I'll have to get the specs on them sometime.
_________________________
Matt
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#174733 - 11/08/2003 16:14
Re: DVD-RAM as a replacement for DAT
[Re: tfabris]
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carpal tunnel
Registered: 30/10/2000
Posts: 4931
Loc: New Jersey, USA
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It would be nice to be able to backup the entire system (OS and all) everyday which is something we could do with huge-ass tapes. DLT seems like the way to go.
At least now I know that when I have a problem there are a bunch of people on the board that have experience with fixing these things.
_________________________
-Rob Riccardelli
80GB 16MB MK2 090000736
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#174734 - 11/08/2003 16:31
Re: DVD-RAM as a replacement for DAT
[Re: robricc]
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carpal tunnel
Registered: 20/12/1999
Posts: 31600
Loc: Seattle, WA
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It would be nice to be able to backup the entire system (OS and all) everyday which is something we could do with huge-ass tapes. If you really want to do that, I can tell you what filter specs to put into ArcServe so it'll ignore the stuff that's being read/written by the OS "live" that would produce errors at backup time. But honestly, I wouldn't bother. I just assume that if the OS drive goes down I'll have to reinstall the OS anyway. I only back up the irreplaceable data, not the OS and stuff I can reinstall. But to each his own.
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#174735 - 11/08/2003 18:06
Re: DVD-RAM as a replacement for DAT
[Re: robricc]
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carpal tunnel
Registered: 24/12/2001
Posts: 5528
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Not sure about the DVD-RAM discs themselves but I've got a few first gen CDROM drives which used caddies to load the discs. It was an absolute pain to have to mess about with them and for some reason even though they've got a shutter, they'd still manage to collect dust and other crud inside.
A big disadvantage is that it used to be/still is that only the single sided discs can be bought without caddies. The double sided ones were all permanently mounted inside the caddy. Another thing is that you can't normally read DVD-RAM discs without a DVD-RAM drive but as it's only to be used as a server backup then you're pretty much going to be reading them on the same machine.
But I agree with everybody else. Go for DLT or Ultrium if you can afford it. It's much more reliable and stores a lot more than a DVD-RAM disc. How big is the disk in the server anyway? If it's bigger than around 4.7GB then it's going to be annoying to have to keep swapping discs.
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#174736 - 11/08/2003 18:26
Re: DVD-RAM as a replacement for DAT
[Re: tman]
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carpal tunnel
Registered: 30/10/2000
Posts: 4931
Loc: New Jersey, USA
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How big is the disk in the server anyway? Currently we have a capacity of about 8GB (three 4.3GB disks in RAID5 array). The stuff that must be backed up takes up about 1GB.
_________________________
-Rob Riccardelli
80GB 16MB MK2 090000736
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#174737 - 11/08/2003 18:30
Re: DVD-RAM as a replacement for DAT
[Re: robricc]
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carpal tunnel
Registered: 24/12/2001
Posts: 5528
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1GB? Pah! Use floppies  I know somebody actually that had the misfortune of needing to move about 600MB of stuff from one computer to another with only floppies...
Oh hmm.... If it's only 1GB then it's up to you really about what backup you use. If you're going for the cheap route then I'd say just buy a DVD-R drive and a stack of DVD-R discs. You burn it and then lock them in the safe and just throw it away when you're done. This way the disc is new and you don't have any problems of how many times you can reuse it and keeping it the discs clean as you're only ever use it once.
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#174738 - 11/08/2003 18:55
Re: DVD-RAM as a replacement for DAT
[Re: tman]
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carpal tunnel
Registered: 30/10/2000
Posts: 4931
Loc: New Jersey, USA
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1GB? Pah! Notice I used the term must be backed up. This indicates that this is the bare minimum of ultra-important data. Our current backup process uses nearly the entire 2.0GB DDS1 tape. Anything over that 1GB is mainly crap that just makes it easier for me to get the system running again.
My machine has all the literature, product photos, and desktop publishing stuff on it. Currently, I am using DVD+RW to back that up onto two discs (about 8GB). With the DLT, I could use that huge amount of backup storage to back that up every day. Currently, I back that stuff up whenever I have nothing better to do and the BBS is slow. So, I think I could use at least 10GB if I wanted.
_________________________
-Rob Riccardelli
80GB 16MB MK2 090000736
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#174739 - 11/08/2003 20:13
Re: DVD-RAM as a replacement for DAT
[Re: robricc]
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addict
Registered: 20/11/2001
Posts: 455
Loc: Texas
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Have you considered a removable or Firewire hard disk solution on which you can Ghost the drive you want to back up?
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#174740 - 11/08/2003 20:33
Re: DVD-RAM as a replacement for DAT
[Re: blitz]
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carpal tunnel
Registered: 30/10/2000
Posts: 4931
Loc: New Jersey, USA
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Yes, but this is not as portable as a tape or CD. In case there is a fire, the accountant takes the previous night's backup home with her every night.
_________________________
-Rob Riccardelli
80GB 16MB MK2 090000736
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#174741 - 11/08/2003 20:37
Re: DVD-RAM as a replacement for DAT
[Re: robricc]
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Carpal Tunnel
Registered: 08/02/2002
Posts: 3411
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What is the average daily delta that would need to be transferred? And the net connection? I wonder if an online backup might work for you (eg www.connected.com )
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#174742 - 11/08/2003 20:44
Re: DVD-RAM as a replacement for DAT
[Re: genixia]
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carpal tunnel
Registered: 30/10/2000
Posts: 4931
Loc: New Jersey, USA
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We just dumped our T1 in favor of a 1.5/384 ADSL line since we are no longer hosting anything on-site. I'm not postive that 384Kb is too slow for 2GB/day, but it seems like it to me.
Actually, it would only be slow if you were sitting there watching it. We run our backup at 1AM currently. Maybe we would have to run it earlier to make sure it was done by the morning? In the end, this seems like it would be more expensive as long as the DLT tapes last as long as Tony says. I will look into this and other services more though. Thanks for the idea!
_________________________
-Rob Riccardelli
80GB 16MB MK2 090000736
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#174743 - 11/08/2003 21:01
Re: DVD-RAM as a replacement for DAT
[Re: robricc]
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carpal tunnel
Registered: 20/12/1999
Posts: 31600
Loc: Seattle, WA
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Genixia's got a point.
The online backup site doesn't necessarily need to copy all 2 gigs every night. If the changed data is in a bunch of small files (instead of one huge database file), then you actually only need to back up what's changed, and 384k might be PLENTY for that.
I personally do my backups as a full file-by-file backup every night because I can. It means that in order to get the latest file backup, I need only one good tape out of all the grandfathered copies rather than having to worry about "delta" tapes. And it allows me to go back to any one date within the last few weeks (or a more fuzzy date from within the last year) and pull any version of any file without having to fish through file-change records.
But if you're using an online backup/mirror, then that trickle strategy makes more sense.
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#174744 - 11/08/2003 21:53
Re: DVD-RAM as a replacement for DAT
[Re: tfabris]
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carpal tunnel
Registered: 10/06/1999
Posts: 5916
Loc: Wivenhoe, Essex, UK
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I do my backups for my home systems via an online backup over 1024/256 DSL. I currently have 30GB that is protected this way, which works fine because the daily changes to files are rarely more than a couple of hundred MB.
I don't use an online backup service, I have a cheap, quiet Linux box installed on a friend's DSL line and I use a rsync to do the backups at 4am every morning.
I sleep much easier at night now I'm not relying on crappy tape drives (didn't have even DAT) to backup my life's data...
P.S. I'm wishing I had put more than a 120GB disk in the remote Linux box though, as my Canon 10D camera seems to be eating about 1GB of the space a month !
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