The Host NIC (Initiator) and the array SP port (Target) should negotiate the frame size - if the array is at 9000 and the host is at 9014 and the switch supports MTU 9000, it should work - make sure the switch is really enabled (if the switch supports larger than 9000 - try a larger MTU setting on the switch - it's just a pass through).  See Support Solution emc151113 - this provides information about MTU support on the EMC arrays. There is also a small test you can use to see if the frames are being passed correctly.  glen
Hey Folks,  So I have the following:  HP DL380 G5 server (WIndows 2008) with an HP NC7170 NIC card I have an AX4-5i w/Flare code 23 HP Procurve 2810-24G switch  I inherited this setup.    Now, the switch has jumbo frame support turned on for the two subnets supporting the SPA/SPB networks.  The Navisphere Express shows all for iSCSI connections configured with 9000 MTU.  This weekend I re-configured / changed the "Jumbo Packet" setting in the device manager to 9014 (The choices are 9014, 4088, 16128, or disabled).  It was set to disabled.  When I changed the setting to 9014 (since there is not actually a 9000 setting), and rebooted, everything that gets pulled off of the Clarion array is corrupted.  If I switch it back to disabled (and reboot again), everything is working again.  Any suggestions?  Thanks,  James
HP NC7170 NIC card & Jumbo frames with AX4-5i