BladeSystem Virtual Connect
Showing results for 
Search instead for 
Did you mean: 

Switch ports configuration for iSCSI storage and Virtual Connect Flex-10

Trusted Contributor

Switch ports configuration for iSCSI storage and Virtual Connect Flex-10

Wonsuk was looking for some advice with iSCSI storage




I am developing a ref configuration set up guide for XenServer and P4500 Lefthand iSCSI storage.

Ref architecture will be that XenServer is running on BL460 and dual Virtual Connect Flex-10 modules will be installed on C7000. Flex-10 will emulate 8 NICs on each blade server.

Procurve switch will be placed between the  VC and P4500 lefthand iSCSI boxes.


According to Citrix switch configuration recommendation article (

  1. Enable PortFast on XenServer connected ports.

          a. Eenable PortFast with caution, and only on ports that do not connect to multi-homed devices such as hubs or switches.

  2.  Ports used for storage should have PortFast enabled.


I am wonder because we place VCs before Xen host servers if I should not enable PortFast feature.


Thanks for sharing your insight in advance.




Murthy had some info:




It is recommended to set PortFast feature on the external switch even for the ports connecting to VC’s uplinks.


If in case, customer is concerned, then they can enable BPDU guarding on these ports.




Any other input or suggestions for Wonsuk?

Trusted Contributor

Re: Switch ports configuration for iSCSI storage and Virtual Connect Flex-10



Cisco's portfast or ProCurve's RSTP is part of Spanning Tree Protocol configuration which help to prevent network loop.


When a cable is connected or a switch is powered on, switch ports have to undergo different modes before becoming active port (Blocking, Listening, Learning, Forwarding). Each mode is having its own timers which will take approximately 50 secs before a port to reach forwarding mode. When you enable Cisco's portfast or ProCurve's RSTP (Rapid Spanning Tree Protocol) switch ports will take only 20 secs to become active. It is not recommended to configure Cisco's portfast or ProCurve's RSTP on a port which connect to another network switch's uplink ports (since it skips those mode's loop detection, is not posible).


Since VC is not a network switch, there is no possibility of loop. So portfast or RSTP can be configured on the ports which conecting to the VC.



R. Ramu