etherchannel - aggregation

[carl_townshend]

Hi all,i was told that when using etherchannel or any other kind of multilink connection that if you had 2 links both running at 100 meg and you grouped them together, it does not double the bandwidth to 200 meg as losd shares between them, is this true ?

[fargier]

Hi,

The FEC or GEC (fast/Giga etherchannel) double your bandwith is you use two port in the group. But by default it use mac-addresses to the load sharing. It's a logical && or || i don't remember.

In fact, if you have only on mac-addresse that pass trought your FEC or GEC, you use only one channel. So you only have single bandwith.

You can change many think in the etherchannel and you can group more than 2 port.

Ludo

[Anand Narayana]

Hi Carl,

Ethernchannel doubles the bandwidth in L2 switch & only on L3 routing it load balance by having two static routes pointing to same destination.

verifying etherchannel

show interface port-channel 1, there i will show the BW 20000 Kbit, if two physical ports are clubbed together.

where as in L3 load balancing

ip route 192.168.1.0 255.255.255.0 10.1.1.1

ip route 192.168.1.0 255.255.255.0 10.1.1.2

i hope ur clear now.