DSS FC write problems

[hughesmikea]

I changed the switch ports for DSS from auto negotiate to 4GB. No difference. I/O guard is set to auto.

I did not change the ports for Xen, because I do not have this issues from Xen to SANmelody on the same switches.

thanks
mike

[symm]

Hi hughesmikea

What RAID level are you using?
Can you try enabling cache and read ahead on your RAID controller.
how much RAM do you have ?
Is it locking up or is the write fast in the beggining and then slowing down?

[Robotbeat]

Have you compared it to iscsi or nas performance on the same disks/dss?

[hughesmikea]

gentlemen,

Server is a brand new PowerEdge 2970 with a PERC 5/i RAID controller and 4GB RAM
(6) 1TB SAS Drives in a RAID 5 with writeback cache enabled (default)

Just created an iSCSI volume and attached my PC to it. I copied a 2.5GB file across smoothly.

When copying acrosss FC, the copy has an initial burst, then pauses for a while, then bursts again, then repeats until complete.

mike

[To-M]

Forget to ask or maybe you did test this already but what about directly connecting w/o the switch. I know that the Datacore you didn't have to do this but just a thought.

[symm]

Hi hughesmikea

can you manually set the I/O Gaurd

[hughesmikea]

Good Morning,

OK, I went port to port from Xen to DSS and it worked fine. Then I wen back through the switch and it is NOW WORKING. No changes were made to the FC HBA's or switch.

Any thoughts on how this could be??

mike