Cisco UCS: vHBA bandwidth

I never really understood how Cisco UCS vHBA are configured in regards to bandwidth (coming from a FC background).

Finally I got it spelled out for me like I was five…..IT IS JUST A ETHERNET PORT (yes yes…I knew that. But I really thought there was some more magic involved). IT JUST SYNCS ON THE SAME SPEED AS THE FEX PORT IT IS CONNECTED TO. That would mean if you have a blade with a VIC, a 6332 FI and a 2304 FEX and you do not have the port expander it will be configured as a 20Gbit port (2x10Gbit) with a single flow maxing out at 10Gbit/s (to the FI…not taking into account break out speeds to your ethernet and storage network from the FI). If you have the port expander for the VIC you get native 40Gbit/s if you are using the 2304 FEX and the 6332 FI (single flow can reach 40Gbit/s from the FEX to the FI).

I had a real duh! moment there.

Now it is out there! Hopefully this can help some poor soul out there. I googled my life away for couple of days and did not find a real answer.


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