COnfiguration Suggestion - Etherchannel

Robert Blayzor rblayzor at inoc.net
Wed Jul 28 03:09:37 UTC 2004


Mike Sawicki wrote:

> I would use method #2 above.. L3 FEC produces better balancing
> results as it is flow based, rather than mac-based.  I'm not 100%
> certain that using the SVI interface would not produce a proper
> balance, but I doubt it.   Using method one I would expect only one
> of the links to be used.
> 
> Use method 2 especially if you mean this to be a L3 handoff to the
> customer.

What Mike states is correct about the layer2 vs layer3 load balancing:

http://www.cisco.com/en/US/customer/products/hw/switches/ps700/products_configuration_guide_chapter09186a008007f648.html

Understanding Load Balancing
EtherChannel balances traffic load across the links in a channel by 
reducing part of the binary pattern formed from the addresses in the 
frame to a numerical value that selects one of the links in the channel.

EtherChannel load balancing can use either MAC addresses or IP addresses 
and either source or destination or both source and destination 
addresses. The selected mode applies to all EtherChannels configured on 
the switch.

Use the option that provides the greatest variety in your configuration. 
For example, if the traffic on a channel is going only to a single MAC 
address, using the destination MAC address always chooses the same link 
in the channel; using source addresses or IP addresses may result in 
better load balancing.

-- 
Robert Blayzor
INOC, LLC
rblayzor at inoc.net



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