etherchannel 以太网通道
PAgP 思科私有协议
LACP IEEE802.3ad协议
静态etherchannel协议
互不兼容三种协议
show ethenchannel summary
端口状态
interface range f0/1 - 2
channel-group 1 mode active
exit
interface port-channel 1
swithchport mode trunk
switchport trunk allowed vlan 1,2,20
show interface port-channel 1
show etnerchannel port-channel
