Hi guys,
        I'm getting some pretty poor performance from my Netbackup setup. My 
current system is:

An STK L700 robot with 6 LTO tape units - four of which are connected to a 
fiber/scsi bridge. This is being driven by a Sun E450 running as a media and 
master server. Also connected to my SAN is a 6800 and an E220, these are all 
configured as media servers and SSO has been configured across all systems.

All Sun systems are running Solaris 8. This has been patched with Sun's 
recommended patches. Sun patch 110539-04 (which appears to be a repackaged 
Veritas J0850645a patch) has been installed on everything.

Everything appears to _work_, it's just going unacceptably slowly. We can 
achieve approx. 10Mb/sec to the tape units using ufsdump, when we run stuff 
over netbackup, we get 200kb/sec. It takes a couple of hours to back up a 
2gb file system:-x


I'm 100% sure all data is running over the SAN, I am sure of this as only 
the server I'm backing up has any tape IO activity. I've also run a sniffer 
over the ethernets and there is not a huge amount of traffic between them. 
I've also checked the lights on the SAN switch - only the server running the 
backup and the fibre/scsi gateway's interfaces are active.


I was recommended by Veritas to add the following entry into my st.conf 
file:

"SEAGATE ULTRIUM06242-XX","Seagate LTO","SEAGATE_LTO";
SEAGATE_LTO = 1,0x36,0,0x1d639,4,0x00,0x00,0x00,0x00,1;

This made no difference to my throughput.


Anyone got any ideas - defiantly a few beers for information leading to 
resolution of this one.

Cheers -

Lawrence Billson




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