免备案网站制作站长网站

链路聚合:

链路聚合:

链路聚合 （Link Aggregation），也称为端口捆绑、端口聚集或链路聚集，链路聚合是将多个端口聚合在一起形成1个汇聚组，以实现出/入负荷在各成员端口中的分担。从外面看起来，1个汇聚组好像就是1个端口。

优点:

提高链路带宽

提高可靠性：同组成员彼此动态备份

要求:

加入链路聚合的端口的带宽，速度，vlan等设置都要一样

链路聚合	手工模式	LACP	PAGP
名称		链路聚合控制协议（IEEE802.3ad）	端口聚合协议
开放性		开放标准	思科私有
标准		Etherchannel and IEEE 802.3ad	Etherchannel
模式	Static On Mode	Active/Passive	Auto/Desirable

SW1和SW2的f0/20-f0/23作为链路聚合的端口，PC1和PC2作为vlan1互相通信:

SW1:

Switch(config)#int range f 0/20-23  #设置f0/20-23端口四个端口设置LACP
Switch(config-if-range)#channel-protocol lacp #设置链路聚合控制协议为LACP(默认值)，LACP为标准协议，pagp为思科私有
Switch(config-if-range)#switchport trunk encapsulation dot1q  #设置帧格式为dot1q,Pt模拟器只有在三层交换机支持，二层教交换机不支持
Switch(config-if-range)#switchport mode trunk  #设置为trunk模式
Switch(config-if-range)#channel-group 1 mode active  #设置指定端口组为1,信道ID为1，模式为active模式,两边只要至少一边时active模式即可Switch(config-if)#int port-channel 1  #创建捆绑接口,就是用channel-group 1加入的相同ID的物理接口，捆绑成一个逻辑接口
Switch(config-if)#switchport trunk encapsulation dot1q #PT模拟器二层交换机不支持，可以不用设置
Switch(config-if)#switchport mode trunk  #设置捆绑接口为trunk模式
Switch(config-if)#switchport trunk allowed  vlan all #trunk默认允许所有vlan通过
Switch(config)#show interfaces port-channel 1  #查看捆绑端口的信息，三层交换机可以查看

SW2也是同样的配置:

SW1:

Switch(config)#int range f 0/20-23 
Switch(config-if-range)#switchport trunk encapsulation dot1q  
Switch(config-if-range)#switchport mode trunk
Switch(config-if-range)#channel-group 1 mode activeSwitch(config-if)#int port-channel 1  #创建捆绑接口,就是用channel-group 1加入的相同ID的物理接口，捆绑成一个逻辑接口
Switch(config-if)#switchport trunk encapsulation dot1q #PT模拟器二层交换机不支持，可以不用设置
Switch(config-if)#switchport mode trunk  #设置捆绑接口为trunk模式
Switch(config-if)#switchport trunk allowed  vlan all #trunk默认允许所有vlan通过

查看端口通道信息:

Switch#show etherchannel port-channel Channel-group listing:----------------------Group: 1
----------Port-channels in the group:---------------------------Port-channel: Po1    (Primary Aggregator)
------------Age of the Port-channel   = 00d:04h:03m:59s
Logical slot/port   = 2/1       Number of ports = 4
GC                  = 0x00000000      HotStandBy port = null
Port state          = Port-channel 
Protocol            =   LACP
Port Security       = DisabledPorts in the Port-channel:Index   Load   Port     EC state        No of bits
------+------+------+------------------+-----------0     00     Fa0/23   Active             00     00     Fa0/20   Active             00     00     Fa0/21   Active             00     00     Fa0/22   Active             0
Time since last port bundled:    00d:04h:02m:35s    Fa0/22
Switch#
Switch#

查看聚合链路状态:

Switch#show etherchannel summary
Flags:  D - down        P - in port-channelI - stand-alone s - suspendedH - Hot-standby (LACP only)R - Layer3      S - Layer2U - in use      f - failed to allocate aggregatoru - unsuitable for bundlingw - waiting to be aggregatedd - default portNumber of channel-groups in use: 1
Number of aggregators:           1Group  Port-channel  Protocol    Ports
------+-------------+-----------+----------------------------------------------1      Po1(SU)           LACP   Fa0/20(P) Fa0/21(P) Fa0/22(P) Fa0/23(P)

两个PC互PING:

链路状态：

交换机之间的线路被捆绑成一个逻辑链路，不会被STP阻断，所有的链路都是开启状态。

手工模式：

设置如图上所示

手工模式设置链路聚合，在设置好端口聚合之前要先把端口关闭，设置好之后再打开端口：

Switch(config)#int range f0/3-4
Switch(config-if-range)#shutdown
Switch(config-if-range)#
%LINK-5-CHANGED: Interface FastEthernet0/1, changed state to administratively down%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/1, changed state to down%LINK-5-CHANGED: Interface FastEthernet0/2, changed state to administratively down%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/2, changed state to downSwitch(config-if-range)#channel-group 1 mode on
Switch(config-if-range)#
Creating a port-channel interface Port-channel 1Switch(config-if-range)#no shutdown Switch(config-if-range)#
%LINK-5-CHANGED: Interface FastEthernet0/1, changed state to up%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/1, changed state to up%LINK-5-CHANGED: Interface Port-channel1, changed state to up%LINEPROTO-5-UPDOWN: Line protocol on Interface Port-channel1, changed state to up%LINK-5-CHANGED: Interface FastEthernet0/2, changed state to up%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/2, changed state to up

sw1：

查看链路信息:

Switch#show etherchannel summary 
Flags:  D - down        P - in port-channelI - stand-alone s - suspendedH - Hot-standby (LACP only)R - Layer3      S - Layer2U - in use      f - failed to allocate aggregatoru - unsuitable for bundlingw - waiting to be aggregatedd - default portNumber of channel-groups in use: 1
Number of aggregators:           1Group  Port-channel  Protocol    Ports
------+-------------+-----------+----------------------------------------------1      Po1(SU)           -      Fa0/1(P) Fa0/2(P)  p代表加入链路汇聚成功，H代表热备份，lacp最多支持8+8备份模式

查看汇聚端口:

Switch#show etherchannel port-channel 1Channel-group listing:----------------------Group: 1
----------Port-channels in the group:---------------------------Port-channel: Po1
------------Age of the Port-channel   = 00d:00h:05m:01s
Logical slot/port   = 2/1       Number of ports = 2
GC                  = 0x00000000      HotStandBy port = null
Port state          = Port-channel 
Protocol            =   PAGP
Port Security       = DisabledPorts in the Port-channel:Index   Load   Port     EC state        No of bits
------+------+------+------------------+-----------0     00     Fa0/1    On                 00     00     Fa0/2    On                 0
Time since last port bundled:    00d:00h:03m:40s    Fa0/2
Switch#

PAGP:

配置都一样，channel-protocol pagp #设置协议为PAGP协议只要有一边设置成channel-group 1 mode Desirable,就可以组成聚合链路