I have a DS4700 with firmware 06.16.82.00 and a SQL cluster in tho windows machines.
We had direct attach connection and we bought two ibm brocade switches.
NOTE: We have made correctly the zonning and we have 3 disk with 12 path(3disks x 4 paths) and 3 RDAC devices.
We can see correctly the disks and the cluster services can start the aplication.
But the performance is now terrible and the SQL has lot of failures.
When we reconnect it with direct attach, the aplication works properly with no failures.
Can anyone help me? why does it work in Direct atach but not with the switches?
Thank you
normaly, when you use a ds4000 direct attached the ports must work with the FC-AL or Fibre Channel Arbitrated Loop Protocol. If you use SAN switches the protocol ist "switched fabric". The difference between theses protocols is huge and have a look on wikipedia for more details. The most important point is: Switched fabric is better. You said you have Brocade Switches. Then open the Web Tools ans look at the ports. All connected Ports should be marked with an "F" as a "Fabric Port". I think the DS4000 will switch automaticlly to the right protocol. But I think the Hosts may be logged in as FL-Ports (Fibre channel arbitrated Loop). And this could be a Problem. If you hava Managment Software for your HBA's like "Qlogic SAN Surfer" maybe you can change the Protocol in Windows, if not, you can also reboot the Hosts and open the BIOS for the HBA's.
BTW. If you are on 6.16. FW for the DS4700 maybe you should update. My recommendation is 6.60.22.x with the DS4700 you don't have the need to upgrade to 7.x Firmware.
I have all port in the switch as F ports. I could change the parameter topology in my emulex hba, but i think this works without changing because I see it in the switch.
About the firmware issue, I'm going to upgrade right now... I woul tell you the result
Well I bought two SAN24B-4 switches and the hbas are two port (three years old) lp1100. As i said, this machines are working properly with direct attach for the last 3 years, so the hbas are not new.