tape loader & ntbackup

June 6, 2006 2:34 AM

Network backup question: I need to backup 6 PCs using an 8 tape autoloader (Dell LTO2 T122) and ntbackup. Currently, the simple setup scheduled backups are quite flakey.

Sometimes tapes don't mount (seems to depend on the sequence of powering up the tape drive and backup system pc) or network drives are disconnected and the backups don't happen - yet the task scheduler doesn't show any errors. I need an automated way, probably a script, to make sure the mapped drives are connected and that the removable media is recognized and mounted so this setup can run without me babysitting it. Logging results would also be nice.

posted by srboisvert to computers & internet (15 comments total)

I've also looked at Dell's recommended software (veritas backup exec - damned if I can even figure out what version I would need ) so if anybody has advice on easy to use and inexpensive backup software that can handle an autoloader and reconnecting mapped network drives that would be useful too.
posted by srboisvert at 4:17 AM on June 6, 2006

Are you required to use Windows?
posted by Mr. Six at 4:40 AM on June 6, 2006

Yes.
posted by srboisvert at 7:19 AM on June 6, 2006

Will the company spring for decent backup software, like Retrospect?
posted by drstein at 10:36 AM on June 6, 2006

I would recommend staying away from Retrospect. It does not work reliably, in my experience, losing connections with its clients and its backup tape drives.

Searches of AskMe will show that others' experiences with Retrospect are similarly plagued with misery. You would be better off with Backup Exec, even with all its attendant security problems.

Unfortunately, since you're using Windows, "autoloader" and "inexpensive" do not fall in the same sentence. You'll probably be spending $500-1000 for a workgroup or small enterprise backup package, but if on the other hand you can afford an LTO2 drive then this shouldn't pose too much of an expense.
posted by Mr. Six at 11:03 AM on June 6, 2006

I actually quite like retrospect. I have a 16-tape HP SSL1016, and it works pretty well. I suspect any intermittent problems I have are with the computer, not the software. The clients work reliably too, though I should mention that they are both linux.
posted by hoborg at 12:07 PM on June 6, 2006

Unfortunately, since you're using Windows, "autoloader" and "inexpensive" do not fall in the same sentence. You'll probably be spending $500-1000 for a workgroup or small enterprise backup package, but if on the other hand you can afford an LTO2 drive then this shouldn't pose too much of an expense.

The company is a university research lab - so money is not available for an enterprise package. Or even Retrospect. I was hoping somebody would have scripting chops and have dealt with RMS and ntbackup but I guess most people with these issues can throw money at them and find better solutions.
posted by srboisvert at 12:44 PM on June 6, 2006

Well, I tried using NT Backup with the autoloader at first. It was not... uh... good. If the problem is on the client end and not the interaction between ntbackup and the autoloader itself, then you could script a network backup script that basically updates a local copy of the folder(s) you wish to backup onto the computer with the tape drive, though your mileage may vary depending on the need. If you have an autoloader, chances it may be more than you'd be willing to copy nightly.
posted by hoborg at 1:19 PM on June 6, 2006

The company is a university research lab - so money is not available for an enterprise package. Or even Retrospect. I was hoping somebody would have scripting chops and have dealt with RMS and ntbackup but I guess most people with these issues can throw money at them and find better solutions.

You might make a case for Linux and OSS. Scripting is pretty much a non sequitor where Windows server management is concerned.
posted by Mr. Six at 2:25 PM on June 6, 2006

You might make a case for Linux and OSS. Scripting is pretty much a non sequitor where Windows server management is concerned.

I disagree - scripting in windows isn't as robust as it is in Linux, to be sure, but for something that's actually pretty straightfoward like this, it'll do fine. Add to that the extreme overhaul converting just the backup server to Linux would require (and the incompatibilty of the old tapes), and, well, that's another entire question for AskMe.

For tapes mounting or not, I'm not sure that's something you could tackle with scripting. If it's a SCSI autoloader, you're absolutely right, it should be powered on (and fully started) before starting the backup PC. Another thing that's critical is to make sure it's terminated. It's simple, but I've gone through MANY headaches before thinking to look.

Scripting the backup script shouldn't be too hard, either. Though obviously you can do it with a WSH script, you could also do a majority of it with a batch command. ntbackup has a load of command line switches that should allow you to do what you need to.

Finally, it might be a good idea to consider automating the mapping of drives, via the net use command. This will allow you to troubleshoot a little better, as you don't have to test whether the mapped drive is active, you can just map the drive, run the backup and then unmap it.

It'd be impossible to write something like that without being there or knowing a great deal more about what you're trying to accomplish; if you could post more about how large your backups tend to be it'd help.
posted by hoborg at 3:17 PM on June 6, 2006

The backup tends to be about 100-150GBgb per machine for the monthly normal backup and then pretty variable for the incremental thereafter.

I've currently got it set to backup one machine a day since overlap on the backups isn't really handled with the task scheduler or ntbackup but with a decent script I could stack them which would be nice. I backup each machine to its own tape.

The net use is a good tip though. I've seen one article on the Removable Media Services scripting so maybe I can get it done on my own.
posted by srboisvert at 3:53 PM on June 6, 2006

only a 150 a month? What I would do in this case, then, is to script robocopy to copy over only the changed files from each machine to a temporary directory on the PC with the tape drive and just back it up locally. We're only talking about 5GB of transfer per PC per day, so if it's done at night, then you won't have any problems in terms of network usage.

I'm just on my way home, but I think a decent plan for a script would be this:

1.) net use O: \\computer1\share
2.) robocopy O: C:\backup /MAXAGE:6
3.) performbackup.exe C:\backup :P
4.) del C:\backup\*.*
5.) net use O: /d

then the next day the computer in question would just be computer2, etc. In fact, you could have the batch file determine which day it is and then get the appropriate computer's files. With a plan like this, it might even be possible to have all 6 computers backed up nightly, and thus reduce your recovery failure chances and bandwith per machine.

I'll look into it more deeply tomorrow, if you'd like.
posted by hoborg at 5:11 PM on June 6, 2006

We're only talking about 5GB of transfer per PC per day

Actually, it isn't like that. I'm backing up fmri data. Most of the machines have around 100-150GB of data on them at any one time. Changes in the data can be sudden and large when new scans are added or analysis are run.

Currently I do a full 'normal' backup during the first week of the month and then incremental backups of each machine each week (Swapping tape sets each month). The annoyances seem to be due to the either the tape drive not knowing what's in it - probably related to how the machines are started - and the networked drives being disconnected.

I can't copy to the backup machine because it won't have enough room - it isn't a dedicated machine.

The things I have to sort out is how to use the 'net' command with a password in a script without storing the password in plain text and some basic logging and interaction along the lines of :

Start up machine X:
and
Success or Failure

and so on since the computers are all powered down every night.

It would also be nice if I could figure out how to script RMS to let me know if the autoloader is in the correct state ..
posted by srboisvert at 1:35 AM on June 7, 2006

Yeah, that is a bit more complicated. As for the tape drive being unaware of what's in it, like I said, it's probably SCSI and it definately has a power-on order, and will need to be terminated.

I generally solve the password issue by creating a user on the client machine called Backup who only has read access to that share at certain times (at night, for example). If the data you have is of secret nature that won't work for you.

Finally, if the machines can wake-on-lan, you should be able to send a string to their network cards that turns them on. And with shutdown.exe you should be able to turn them off, but the problem is one of timing. A simple batch file isn't going to know how long the backup takes.

I know this isn't the answer you were looking for, but Retrospect might be a viable alternative. With the client software it installs on the other PCs, you don't really need to worry about security, plus it backs up only what's needed. The drivers for my device (Ultrium 2) that came with it are much more reliable than the ones that came with the drive itself. It's about $500 for the single server edition. Waking the machines up will still be an issue, though. Worth looking into.
posted by hoborg at 8:08 AM on June 7, 2006

If you bought "enterprise"-category servers and workstations, it is likely you have network adapters in them that listen to Wake-on-LAN packets, which might help you in your scripting endeavors.
posted by Mr. Six at 11:55 AM on June 7, 2006