CX300i - iSCSI problems when connected through a switch

Question

I've got a CX300i, Cisco Catalyst 4503, QLA4050c and a Dell PE860. I've been able to SAN install the OS if I direct connect the QLA to one of the four iSCSI ports on my CX. If I try to connect them both to the Gig ports on my Catalyst the QLA takes much longer to find the LUN's and I get a blue screen half way through my windows install. If I complete the windows install while being directly connected to the EMC then try to boot the OS (SAN Boot) while connected via a switch it reboots the server just before going into the GUI (IE it says windows is loading and as the screen flickers to show the GUI it reboots instead). If I direct connect it to the EMC iSCSI port it boots up just fine. Thanks, Joshua N. Vautour

JoshuaV1 · Answer

Hi,
I finally found a solution to this problem. It took working with EMC for 14 hours and having them finally tell me what I'm doing is unsupported

. Although this didn't directly help it did however tell me that the problem was not my host and not my cx300i because they checked all collect outputs and what not.

It turns out that when windows initializes it resets the interface of the iSCSI HBA which wouldn't cause a problem directly connected but since it was switched and the interface reset the spanning-tree protocol was keeping the interface from talking for about 20-30 seconds which caused windows to die. You simply need to enable spanning-tree portfast on the interfaces that your hosts connect to.

Thanks,

Joshua N. Vautour

CLARiiON

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