blade to IO module port for B-250

[e-chuah]

Hi,  If I have 4x10GE to the Fabric interconnect, The blades (B200) are hard wired to use the 4x10GE connection in the following manner -Blade1 – IOM link 1 -Blade2 – IOM link 2 -Blade3 – IOM link 3 -Blade4 – IOM link 4 -Blade5 – IOM link 1 -Blade6 – IOM link 2 -Blade7 – IOM link 3 -Blade8 – IOM link 4  If I have 4x10GE to the Fabric interconnect, The blade (B250) blade number is 1,3,5,7. How will the blade use the uplink? If it follows the B200, then it looks like -Blade1 – IOM link 1 -Blade3 – IOM link 3 -Blade5 – IOM link 1 -Blade7 – IOM link 3 THen in this case, link 2 and 4 will not be used?  Can anyone confirm ?  THanks Eng Wee

[kschroed]

The wiring is fixed to the chassis slots so as you have pointed out in your B200 mapping. With the B250 since it is full width it will get access to all available IO Paths divided between the two mezzanine cards.  So its more like this:

Blade1 Mez1 – IOM link1, Blade1 Mez2 IOM Link2

Blade3 Mez1 – IOM link3, Blade1 Mez2 IOM Link4

Blade5 Mez1 – IOM link1, Blade1 Mez2 IOM Link2

Blade7 Mez1 – IOM link3, Blade1 Mez2 IOM Link4

[e-chuah]

Hi Ken,  Thanks for the clarification. So if i my B250M has only one Mezz card, then IOM link2 and IOM link4 will not be used even if it is connected.  In addition, if i my B250M has only one Mezz card, and two links from IOM to fabric interconnect, then i should connect my two uplinks on port 1 and port 3 of the IOM (since 2 and 4 will not be used)  I believe that should be the case. Pls advise if u think otherwise.  Thanks again Eng Wee

[kschroed]

I'm not sure the IOM uplink connectivity allows for that type of patching.  You have 3 options for Patching as I understand it Port 1, Port 1+2, Port 1-4.  If you only have 2 x IOM uplinks per fabric to your chassis with the B250 and one mezzanine card per blade, I'm not sure what the optimal configuration would be.

[e-chuah]

Hi Ken I did a check with the Cisco account team and the workaround is as follows: Slot 1 B250 blade - Mezz installed in slot0 (use IOM uplink 1) Slot 3 B250 blade - Mezz installed in slot1 (use IOM uplink 2) Slot 5 B250 blade - Mezz installed in slot0 (use IOM uplink 3) Slot 7 B250 blade - Mezz installed in slot1 (use IOM uplink 4)  with this, we will be able to load share the link. Will test it out in the lab using 1.2(1b) and see if it works.  Rgds Eng Wee

[e-chuah]

Hi..  Just an update. Did a test in the lab. The workaround that i sent in the previous post works.  Rgds Eng Weee