How can I determine which FC-AL interface is more loaded.

[Evgeny Filippenkov]

Hi All.
My K370 system with HP-UX 11.00 has 2 FC-AL interfaces. Some disks are connected to each inteface. I want to know which interface is more loaded. Of course, I can add data from "sar -d", but I hope I can see it immediately.
For example netstat shows number of packets transfered by each network interface. Is there exist any similar command for FC-AL interfaces.
I tried to use fcmsutil, but I could not figure out their output.
Any suggestion ?

[Eugeny Brychkov]

Evgeny,
fcmsutil (or tdutil) is correct utility to use. There are a lot of possible options, see 'man fcmsutil'. I remember there're some may be useful for you:
fcmsutil /dev/fcmsX stat
fcmsutil /dev/fcmsX devstat all
Generally, if you're concerned about 'load balancing', then you should check all FC disks (devices) used by OS and 'load balance' them between server HBAs assigning primary path to some LUNs using one FC HBA and other remaining LUNs using another HBA. But it's not so simple like splitting LUNs in two sets by fifty-fifty, you should consider LUNs usage also, so in given timeframe both HBAs got used almost equally
Eugeny

[Zeev Schultz]

Eugeny,
It's not important if this is scsi or fc.The correct topology is a result of monitoring load
on your system.Once you split the load correctly - it should work ok.However,if you suspect fc HBA to be the bottleneck use fcmsutil.

Regards,

[monasingh_1]

If you have EMC, then the new control center tells you about the throughput and number of IOs on the channel.

[Evgeny Filippenkov]

Well, sorry for delay I was sick out. I've started fcmsutil but could not understand its output. You can see sample of fcmsutil output in attachment. Can anybody explain me what it does mean ?

[Eugeny Brychkov]

Output looks incomplete. Anyway, driver gathers data since last reboot, and doing fcmsutil for both HBAs and looking for field like 'processed requests' and comparing this value between HBAs may give you an idea of overall packet throughtput. In addition you can make a 'snapshot' of fcmsutil just before rush hours and then take fcmsutil after rush hours, substract and compare processed requests values
Eugeny

[Jeff Schussele]

Hi Evgeny,

The stats to look at in that output are:

ocq_seqs_comp (outbound)
inb_sfs (inbound)

The key to comparison is to clear the stats & read them for both cards at the same time so they'll accumulate over the same period.
If they end up close to each other over the same period, then you're balanced.

HTH,
Jeff

[Evgeny Filippenkov]

Thanks. All HW path have worked after system was rebooted.