Best practice for Cisco switch to VMWare host connectivity?

[Daniel Maloney]

Hi! I was wondering if there is a best practice for Cisco switch to VMWare connectivity? I've seen people mostly do Etherchannel but what about load balancing? Which etherchannel load balancing method is the best?

Please share your experience if possible.

Thanks!

[Jon Marshall · Accepted solution]

You pick the load balancing method that makes most sense and is supported by your devices.

Generally speaking source and destination IP address is a good method to choose and this is quite effective in spreading the load across the links.

Bear in mind that for a specific flow all traffic will be sent on the same link and etherchannel cannot use multiple links for the same flow.

How the flow is defined is determined by the load balancing method in use.

So if you use source and destination IP and you have a client connecting to the server the traffic will only use one link out of the etherchannel.

If the traffic is greater than the bandwidth of that link etherchannel cannot use any of it's other links.

But if there was another client connecting to the server etherchannel could use another of it's links although it is not guaranteed it will.

It is not really load balancing because there is no feedback mechanism in etherchannel ie.when it works out which link to use it takes no account of how heavily loaded the links are.

Jon

[Ganesh Hariharan · Accepted solution]

Hi! I was wondering if there is a best practice for Cisco switch to VMWare connectivity? I've seen people mostly do Etherchannel but what about load balancing? Which etherchannel load balancing method is the best?Please share your experience if possible.Thanks!

Hello Daniel,

What we deployed and implemented in our DC for all VMWare ESXi host connectivity with Cisco Switches is Multi ether channel deployment for dual homed.

And load balancing hashing we deployed in default in general on all these port channel but certain scenario make to think on optimum use of port channel where application requirement made us to change the algorithm from default to different like src ip and dest ip ..

Hope it Helps..

-GI