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vnic bandwidth question

I have a blade with a VIC 1240. I can attach 6 10GB nics to it for 60GB bandwidth. My question is, If I only connect 2 nic to it will use 30GB bandwidth each or do I have to define all 6 to utilize all the bandwidth?



Re: vnic bandwidth question

Hi David

Before you consider the virtualized part of the adaptor, you should consider the hardware connectivity.

Following configurations are possible (lets assume B200-M3)

1) VIC-1240 (MLOM) plus 2204 (IOM)

2) VIC-1240 (MLOM) plus 2208 (IOM)

3) VIC-1240 (MLOM) + Extender plus 2204 (IOM)

4) VIC-1240 (MLOM) + Extender plus 2208 (IOM)

the resulting bandwith (adpator - chassis backplane - IOM) are the following

1) dual 1 x 10G

2) dual 2 x 10G

3) dual 2 x 10G

4) dual 4 x 10G

If you now create n x vnics and m x vhba in your service profile, they are multiplexed over the available physical bandwith above; so you will have oversubscription !

Lets assume you have a ESXi server with 2 vnics, one connected to fabric a, the other to fabric b. Lets also assume you have configuration 2) or 3); then your vcenter shows a vnic of 20G

You control the oversubscription of the adaptor configuration; eventually, you could also create QoS policy and attach it to a vnic.

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