Etherchannel question

grag

I'm hoping someone can explain the meanings of some information after issuing the show etherchannel port-channel command on a switch.

There are some columns titled Index, Load, EC state and No of bits. I think these refer to how the switch is load balancing over the ports within the channel and how much data is transmitted over them, but I would like a breakdown of them. Can anyone help please? Thank you.

jgthompson90

It has to do with load balancing, to an extent which you probably won't deal with until you reach your CCNP.

Index = Order for which that interface will be used to disperse traffic. And I'm sure this somehow converts to binary to dictate said order
Load = Traffic load on each link, in Hex. Where the decimal conversion would equal a total of 255 = 100% utilization. (Say the number on Load is 55, it would be 0x55; AA would be 0xAA)
EC State = Ether channel state (active, desirable, automatic, etc..)
No (number) of Bits = Number of bits used in the hash algorithm for each physical interface.
2 ports = 4:4
3 ports = 3:3:2
4 ports = 2:2:2:2
5 ports = 2:2:2:1:1
6 ports = 2:2:1:1:1:1
7 ports = 1:1:1:1:1:1:1

It is best to load balance with 2, 4, or 8 ports.

trac0de

Hey guys,

Is that right that EtherChannel can use MAC for load balancing (can use IP or port as well) but if the traffic goes to a single MAC address based on destination MAC address results in the choice of the same link in the channel each time. So it doesn't load balance between more links in the channel. For example, multilink PPP does by default load-sharing (if there are two lines in multilink and a packet has to be sent over the PPP will send one packet to the first than second to the other line). That's my few cents regarding load-balancing/sharing