EtherChannels

Finally a topic I was looking forward to a little bit!
Etherchanneling is the "logical" bundling of 2-8 physical connections between switches. Also known as link aggregation. Etherchanneling provides greater throughput (i.e. bandwidth), and bypasses some of STP shortcomings such as convergence time (STP treats etherchannels as 1 connection).
There are 2 main protocols within Etherchanneling

• LAgP (link aggregation protocol

Active mode- switch will initiate bundling of channels with remote switch
Passive mode- switch will wait for remote unit to initiate bundling
on (no negotiation)

• PAgP (port aggregation protocol

Dynamic (desirable)- switch will initiate bundling of channels with remote switch
auto- switch will wait for remote unit to initiate bundling
on (no negotiation)

To properly channel the port group # must match on both switches (i.e. the port or channel group number. Also, the remote device id must also be the same (i.e. it can only be switch to switch, not 1 switch to multiple switches).

Commands I saw:
(interface)channel-group [#] mode [auto, desirable, active, passive, on]
show interface port-channel [#]
show pagp [#] neighbor
sho etherchannel brief
sho etherchannel detail
sho etherchannel summary

Cool class!