Load Balancing

[nakhtar.ciena]

We all know that all the switches comes with port-channel load-balance “src-mac”. We have a netapps and we have made the etherchannel with netapps using 3 gig ports, we checked the documentation, netapps only support port-channel load-balance src-dst-ip.

If we apply “port-channel load-balance src-dst-ip” command to the switch to use with netapps,it will change the mode of all the etherchannel including the trunck etherchannel we have used to give the uplink to this switch.

My question is, if we will use “port-channel load-balance src-dst-ip” in this switch and all the other switches remain using “src-mac”, would there be any issue in our network or would this switch disconnect from network or give any performance issue while using “port-channel load-balance src-dst-ip” in this switch for netapps.

Thanks in advance,

[Ryan Carretta]

This shouldn't make a difference.

That being said, I don't think you need to make any changes. The load-balance hash method is used only when making a decision on how to send data, not how to receive it. The NetApps should receive data on any link irrespective of how the switch sends it, so I don't think you should need to change the switch method if you don't care to. Similarly, if the NetApps sends data, the switch should receive it regardless of which link it's received on.

Additionally, a quick correction. The src-mac algorithm on most platforms should only be used for non-ip ethernet traffic. IP traffic by default on most platforms should be calculated by src ip ^ dst ip. To be sure you can try a 'show etherchannel load-balance'.

[nakhtar.ciena]

it shows:

EtherChannel Load-Balancing Operational State (src-mac):

Non-IP: Source MAC address

IPv4: Source MAC address

IPv6: Source IP address

[Ryan Carretta]

Okay, then you are in fact doing src-mac for IP traffic as well. What I mentioned should still apply as far as the application traffic goes. Either way, if you want to change it you shouldn't need to change it anywhere else if you don't want to. Totally up to you. =)