Question : Slow performance in netware cluster

We have a 2 node Novell Cluster with 2 x IBM x346 servers connected to IBM FastT600 SAN.  We have a 3rd node to add to the cluster, an IBM x3650.  On loading Cluster Services on the 3rd node the performance of the data volumes hosted on the other 2 nodes in the cluster slows right down.  When we unload cluster services on this 3rd node the speed of the data volumes returns to normal.

All servers are running Netware 6.5 SP7 with Cluster Services Version 1.80.04.
The 2 x IBM x346 servers each have 2 x Qlogic QLA2340s.  The IBM x3650 has 2 x Qlogic QLE2460s.  All 3 servers are running the QLogic QL2X00 HAM driver  version 6.90.15.  All 3 servers connect to the FastT600 via 2 x IBM 3534-F08 SAN Fibre Channel Switches.

Does anyone have any idea as to what might be causing the slow down in performance.  Any help would be very greatly appreciated.

Answer : Slow performance in netware cluster

Hmmm.... interesting.

I'd ensure the QLogic BIOSes all have similar settings for timeouts and the like. Given what you've described, it does sound like a problem rooted in hardware. You don't happen to have a spare QLA2340 that you can drop into the 3650, do you?