I have a Hitachi USP 100 array configured for lunix DM multipathing. I don't want to use "multibus" policy since I am testing one of our company's product which specifically requires me to turn off load balancing/round-robin. So I intend to use "failover" policy even though I have Hitachi USP 100.

I have 2 HBAs, 2 array ports for my HITACHI Tagmastore array. Is there a way I can set a "preferred" path for I/O or redirect I/O from one path to another?

multipath output :
------------------
mpath0 (360060e800427dd00000027dd00003f80)
[size=500 MB][features="0"][hwhandler="0"]
\_ round-robin 0 [prio=1][active]
\_ 2:0:0:0 sdc 8:32 [active][ready]
\_ round-robin 0 [prio=1][enabled]
\_ 3:0:0:0 sde 8:64 [active][ready]

iostat displays that the I/O is routed through the path "sdc". Is there a way to route it through "sde" ? And I want to be able to do this without any I/O disruption.

extended device statistics
device mgr/s mgw/s r/s w/s kr/s kw/s size queue wait svc_t %b
sdc 0 4625 0.0 74.4 0.0 4700.9 63.2 36.6 492.9 10.9 81
sde 0 0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0
dm-2 0 0 0.0 4700.9 0.0 4700.9 1.0 2364.9 503.1 0.2 81
dm-4 0 0 0.0 4700.9 0.0 4700.9 1.0 2364.9 503.1 0.2 81

Also why do I see I/O on dm-2 and dm-4?

How would I re-direct I/O to a specific path? When I am testing my product, I will be presenting more paths to the USP 100 LUN and I want to be directing I/O to the newly presented path.

Basically I need I/O routed through only one path and I want to be able to choose which path I can route I/O through.

Thanks again for the help.