Veritas and STK L700

[Michael Peddycord]

We have a STKL700 attached to 3 N's with HPUX11 and 1 NT4.0 via a Brocade switch. The N's are media servers and the NT4.0 is the backup master. Occasionally (fairly often) one HP will lock all of the drives so that no other server can access them. We have just installed IPR0206 and when we set the dm_stape.cfg poll inteval to 0, it causes the polling to run continuously. Does anyone have any idea how to get the HP's to play nicely.

[Michael Tully]

The first two things I would do is this.

Disable the EMS monitoring for the tape drives on your 'N''s. The second is to make sure on your 'N' class servers, that the kernel parameter 'st_ats_enabled' is set to '0'.

Attached is a document on disabling the monitoring.

HTH
Michael

[mark davis_6]

I'm currently supporting dm_stape within HP.

Internally, at least, there is no IPR0206 because it turned into HWE0206, so I'm wondering if IPR0106 may have been loaded, in which case there was a bug related to turning polling off for IPR0106. For the latest dm_stape (HWE0206), my experience has been that turning polling off using POLLING_INTERVAL=0 (in the file dm_stape.cfg), works well, so if there is a bug with this I would appreciate any information you may have. Just fyi, the formal process for submitting bugs would be via our Chart defect tracking system, which the HP response center would do based on your inputs. At that point, I get hounded to fix it!

[Peter Brewster]

Hello,

The problem is not unusual. Especially with NT/2K.

OmniServe products monitor drive reservations, create them if needed, and disolve unused reservations. That way (a) all host systems get their fair share, and (b) back-ups are protected against interference.

[Bruno Cunha]

After doing what Michael told you, you must have patch 34_3 of Netbackup installed and touch /usr/openv/netbackup/db/config/ENABLE_SCSI_RESERVE in all Unix Media Servers, in this way you enable SCSI reserve/relase by software (Netbackup) instead of O.S. level.

Thanks