etherchannel load balancing recommend settings

[carl_townshend]

Hi all

I have a netapp filer with 4 x 1 gig ports on it, If I look at stats on my snmp software for the port channel, I never really see more than 1 gig being used.

I have checked and im using the default of src-dest-ip for the load balancing method.

My question is, what is the best method to use?

cheers

Carl

[Akshay Balaganur]

Hi Carl,

There is nothing like a best method. We need to choose a load balancing hash algo based on our traffic pattern and traffic direction.

Lets consider the following example where we have a etherchannel between a switches.

Clients------ Switch A======== Switch B------- Server

We have traffic from multiple hosts going to a single server. And the return traffic is from Single server to multiple hosts.

In this scenarion it would be best to use " source IP or Source MAC" on switch A as the loading balancing method.

And similarly on Switch B , it will best to use "Dest IP or a Dest MAC" as it will evenly distrubute the traffic over the port channel.

Depending on the platform there should be many more ooptions under the hash method. Like you can add a " Layer 4 port number" option if clients are accessing different applications on the server.

Cheers,

Akshay

[Reza Sharifi]

Carl,

Since you are directly connecting to Netapp Filer, it is perhaps a good idea to find out what Data ONTAP uses for load balancing and follow that.  I think Data ONTAP uses IP address base load balancing, but check with your storage guys.  Also, I don't think Cisco recommend any specific algorithm to use as every environment is different.  Most device seem to use src-dest-ip these days.

HTH