loss of tape drives after a while

[Ayman Altounji]

Hi everybody,

Whe have installed for a customer a backup solution made of 2 ESL9326 librairies equipped each with 16 35/70 DLT drives.

The chosen backup software is Veritas NetBackup. Four media servers (DL 580, NT4 sp6a, SSD 4.90) are connected to the librairies, and each of them manages 4 drives in each library.

For some reason, it appears that after about 2 weeks, part of the SCSI connectivity is lost between the NT boxes and the librairies: some drives appear as 'down' in the backup software, and the control panel SCSI applet shows only SOME of the drives.
After having rebooted everything, things go back to normal.
A colleague of mine told me once about quite the same problem on Proliant servers running Netware. After 1 week, they had to reset... The problem was related with the SSD version. An upgrade solved the prob out.

Some ideas on this? many thanks!
frederic

[Ayman Altounji]

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[Ayman Altounji]

We have had a similar situation. We have a TL891 and have 5 Media Servers and one Master server all NT 4.0 SP 6a using Netbackup DC 3.4. We had to upgrade firmware on the SCSI bridge (sorry I'm not the hardware person). Supposedly there was a setting to keep it from readdressing itself or something. Anyway that didn't work.
Apparently there is a known NT issue with readdressing SCSI devices everytime the servers are rebooted. Here is what we were told to do if you have to reboot:
1. Shutdown the tape library and wait 20 - 30 secs. Bring it back up and make sure it is up all the way.
2. Turn off the fibre channel controller and wait about 20 secs. Turn it back on. Takes about 45 secs to come up all the way.
3. Reboot Master server.
4. Reboot Media servers.
5. Make sure Master and all media servers see the tape devices.
This works for us anyway. Good luck