【实验拓扑】
【实验要求】
一般是把核心交换机之间的线路捆绑成Etherchannel（以太通道），防止spanning-tree的情况，解决核心交换机之间的瓶颈。两交换之间最多支持捆绑8条线路成以太通道。既可以配成2层的，也可以配置3层的以太通道。
以下在模拟器中只能配置2层的以太通道
【实验配置】
首先通过show cdp neighbor来查看交换机之间通过哪些接口连接
sw1(config)#do sh cdp neighbor
Capability Codes: R - Router, T - Trans Bridge , B - Source Route Bridge
S - Switch, H - Host, I - IGMP, r - Repeater
Device ID Local Intrfce Holdtme Capability Platform Port ID
Router Fas 0/15 149 R S I 3640 Fas 0/15
Router Fas 0/14 149 R S I 3640 Fas 0/14
Sw1：
sw1(config)#interface range f0/14 -15
sw1(config-if-range)#switchport trunk encapsulation dot1q
sw1(config-if-range)#switchport mode trunk
sw1(config-if-range)#
*Mar 1 00:05:35.095: %DTP-5-TRUNKPORTON: Port Fa0/14-15 has become dot1q trunk
sw1(config-if-range)#channel-group 1 mode on
Creating a port-channel interface Port-channel1
sw1(config-if-range)#
*Mar 1 00:05:46.931: %EC-5-BUNDLE: Interface Fa0/14 joined port-channel Po1
*Mar 1 00:05:47.183: %EC-5-BUNDLE: Interface Fa0/15 joined port-channel Po1
sw1(config-if-range)#
*Mar 1 00:05:49.783: %LINEPROTO-5-UPDOWN: Line protocol on Interface Port-channel1, changed state to up
Sw2:
sw2(config)#int range f0/14 -15
sw2(config-if-range)#switchport trunk encapsulation dot1q
sw2(config-if-range)#switchport mode trunk
sw2(config-if-range)#
*Mar 1 00:06:42.503: %DTP-5-TRUNKPORTON: Port Fa0/14-15 has become dot1q trunk
sw2(config-if-range)#channel-group 1 mode on
Creating a port-channel interface Port-channel1
sw2(config-if-range)#
*Mar 1 00:06:50.931: %EC-5-BUNDLE: Interface Fa0/14 joined port-channel Po1
*Mar 1 00:06:51.199: %EC-5-BUNDLE: Interface Fa0/15 joined port-channel Po1
sw2(config-if-range)#
*Mar 1 00:06:53.675: %LINEPROTO-5-UPDOWN: Line protocol on Interface Port-channel1, changed state to up
我们通过show etherchannel summary来验证
sw1(config-if-range)#do show etherchannel summary
Flags: D - down P - in port-channel
I - stand-alone s - suspended
R - Layer3 S - Layer2
U - in use
Group Port-channel Ports
-----+------------+-----------------------------------------------------------
1 Po1(SU) Fa0/14(P) Fa0/15(P)
以及通过show etherchannel 1 detail 查看具体的信息
sw1(config-if)#do show etherchannel 1 detail
Group state = L2
Ports: 2 Maxports = 8
Port-channels: 1 Max Port-channels = 1
Ports in the group:
-------------------
Port: Fa0/14
------------
Port state = Up Mstr In-Bndl
Channel group = 1 Mode = On/FEC Gcchange = 0
Port-channel = Po1 GC = 0x00010001 Pseudo port-channel = Po1
Port index = 0
Age of the port in the current state: 00d:00h: 05m :50s
Port: Fa0/15
------------
Port state = Up Mstr In-Bndl
Channel group = 1 Mode = On/FEC Gcchange = 0
Port-channel = Po1 GC = 0x00010001 Pseudo port-channel = Po1
Port index = 1
Age of the port in the current state: 00d:00h: 05m :49s
Port-channels in the group:
----------------------
Port-channel: Po1
------------
Age of the Port-channel = 00d:00h: 05m :52s
Logical slot/port = 8/0 Number of ports = 2
GC = 0x00010001 HotStandBy port = null
Port state = Port-channel Ag-Inuse
Ports in the Port-channel:
Index Port EC state
------+------+------------
0 Fa0/14 on
1 Fa0/15 on
Time since last port bundled: 00d:00h: 05m :52s Fa0/15