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Veritas 9 and HP SureStore Dat 40e

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Nov 15, 2001
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I am having problems with my Hp SureStore 40e compression being turned off by something (I think it is Veritas 9.0). I have replaced the Hp drive and the same thing happens. I have used the HP driver and the Veritas driver and the compression is still getting turned off. Is this happening to anyone else? Anyone have an idea what could be causing this? I think I have narrowed it down to two things, either the server (dl380 g2) itself is shutting the compression off or Veritas.
 
When you configure a job to use hardware compression in Backup Exec, BE just sends a signal to the tape drive to perform hardware compression. It is then up to the firmware on the tapedrive to use the algorithm on the chip in the tape drive to compress the data. BE has nothing to do with it at that point.

Check the Soft-write errors in Properties|Statistics for the tape drive in Backup Exec. If you have a lot, they can seriously erode the capacity of your tapes. How you ask? Every time a tape drive encounters a soft-write error, it is fast-forwarding past what it thinks is a bad spot on the tape. Enough of those errors occur and you are fast-forwarding through much of the tape, decreasing the amount of data that can be written to the tape.

Check the same statistics on your tape. Try new tapes. Make sure HP didn't send you a 'refurbished' tape drive. Also check to make sure you are using the most optimum settings for block size, buffer size, etc on that tape drive. Contact HP for those settings.

Good luck!
 
The problem is that I think Veritas is shutting the Hardware compression on the tapedrive off. When I start the Veritas services my tape drive compression gets shut off. I reenable it with Hp Tape and Library tools and again if I enable Veritas services (backup exe device media service)the compression is magically shut off. All the tests I have run point to Veritas. I have used two new Hp tape drives and get the same results so I don't think its a bad drive.


 
Ok, I can't stand it any longer. How do you know that compression is being "turned off". Please explain further, is there some sort of readout on the tape drive telling you this? Are you getting this from a backup job log? Please inform me, maybe I will learn something new.

Thanks.
 
if you are going off of the readout from the job history, I think that's broken in 9.0. It always says there is no compression. But compression is actually happening. The new job reporting xml stuff seems to be a bit buggy, so I'd expect to see some patches for that soon.
 
Qdog,

Hp has a little utility call Hp Tool and Tape Library. It will do device tests like conection, read and write, and compression tests. When I use this utility it will say Compression is disabled do you want to enable it. I say yes and it enables it and runs a test which passes. Once Veritas services are restarted the (backup device media service) and I go test the drive again the Compression is turned off again. If I do not start the Veritas services it will not shut off. No matter what I do the Backup drive will keep Compression enabled as long as I don't start Veritas. Once Veritas services are turned on the compression on the device is some how diabled. I am working with Hp and Veritas to figure out the problem.

Does this now make sence?

 
Have you had any luck with this one I also seem to be having the same problem with Veritas 9 & a HP Surestore Ultrium 230 ?
 
I moved the backup to a different server and it is working now. I am not sure what the problem was, I think it was conflicting with a program. The difference between the servers is great. The server it had problems on is a Compaq Dl380 2 and the Server it is running on now is a compaq 1600 proliant. I have not installed the IDS and antivirus software on the 1600 and am thinking one of those is interfering with Veritas. I was going to try and break it but everything is running so nice now I may wait awhial. What are you running for servers and are you using Antivirus and IDS? Maybe there is a common thread among us.
 
Guys, check out this document.

I know it says UNIX in the title, but it's about the dip switch settings on the underside of the tape drive. The second topic of discussion in the document (you can click on it to link further down in the document) is about switches 1 and 2. They are the switches that control data compression. By default, all dip switches on the drive should be set to ON except for switch number 3. Try switching the second dipswitch off as well to enable hardware compression without host control. This means that even if you tell Veritas to turn compression off, it won't be able to.

You may also be getting faster speeds on the ProLiant because it may be capable to transfering data at greater speeds. HP offers another utility calle PAT (Performance Assessment Tool) which can measure the speed at which the computer is capable of transfering data. Some people will buy a tape drive because of great advertised speeds and then go and install it on a 5 year old server then come back and say that the drive is crap when really it's the server. This utility will also show transfer rates of a few common HP drives, so you can match what your server is capable of to a tape drive that supports those speeds... if that makes any sense. Anyway, here's the link to downloads for the DAT40e (should jump right to Windows 2000, but you can scroll up and down to the right OS. Again, what you're looking for is called "Performance Assessment Tool")

 
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