LTO-2 tapes marked as full with 96MB

[hkuhlmann]

Hi there,

we are using nsr 7.1.Build230 on W2K3 Server (german) on 25 locations. Most of the IBM LTO-2 tapes mark volumes as full, allthough only a few MB have been written. Deamon log shows

"nsrd: media warning: \\.\Tape0 writing: Die Anforderung konnte wegen eines E/A-Ger„tefehlers nicht ausgefhrt werden., at file 2 record 1430"

in english something like "request ... I/O error ... ".

LTO-2 firmware is up to date.

We reduced SCSI bandwidth from 160 to 80 MB/s which seems to be a workaround.

Is this a common problem?

Regards,
Heiko

 

[605]

That's it. I/O errors. If NW can not recover from a write error, it marks the tape full. This is just a precaution as he can not determine the cause exactly. But he can assume a defective media an prevent to use it again.

As NW does not use own device drivers, you must ensure that your hardware works with 'normal' Windows tools. First!

Of course i can not tell you what might be the problem - in general it could be either hard-, soft or mediaware.

In any way, make sure that you have disabled Windows "Removable Storage Manager".

 

[nishai]

I had a similar problem and it occurred with a number of tapes. It progressively got to the point where I had more tapes filling only to 100MB than those filling up completely. I have a Scalar 1000 and use LTO-1 tapes. I had the technician come out and test my drives. It turned out that they all were performing at a degraded mode and had to be replaced. My tape library is thru ADIC and they actually sent me a diagnostic script via e-mail that I was able to run and it was a clear sign that something was wrong with my drives. I would definitely check the hardware.

 

[bamber]

Hi

I would check that the media being used is the same as the hardware.

In your case you should use IBM media with your IBM drives, if indeed they are IBM drives, we had the same problem with our LTO1 drives, we had maxel media but the drives were HP, when we switched to HP media all our problems went away.

Andrew

 

[hkuhlmann]

Right now, we are looking at a block size issue. A technican told us to set the devices to 128KByte and add a value in the registry (HKLM\system\ccs\services\adpu160m\parameters DWORD MaximumSGList=33 decimal).

Setting the SCSI-bus to 80MB/sec solved the problem of new tapes getting filled prematurely. We are only having problems with the LTO-2 tapes, LTO-1 are running without problems on 30+ Servers.

We are in contact with fujitsu-siemens for a solution about driver information.

 

[605]

Well, lookig at the block size is a good idea but it is definitively not causing this problem. A smaller block size would of course decrease the total capacity but not that dramatically.

BTW, 33d x 4kB would cover 128kB.

 

[Nerom]

Hello!

Yours LTO2 are in a Jukebox or are Stand alone drives? Perhaps, you could revised the SCSI chain, cables, drivers, connectors...

bye

 

[hkuhlmann]

Hi everyone,

thanx a lot for your help. We finally found the problem. After disabling removable storage for the LTO-2 device (stand alone) everything was fine. Volumes that where marked as full/defekt are now operating with full capacity. We installed new drivers for IBM Ultrium-TD2 and Adaptec 29160.

There where eventlog entries from removable storage, which led us to the conclusion to disable it for the tape.

Regards,
Heiko