分类
数据通信
故障描述

<div id="content_1">
<p>如图所示，用户将S5700和Catalyst 3560之间绑定了链路聚合，但是绑定链路聚合不成功。</p>

<p>&nbsp;S5700关于链路聚合的配置如下：</p>

<p>#<br />
interface Eth-Trunk22<br />
&nbsp;port link-type trunk<br />
&nbsp;port trunk allow-pass vlan 2 to 4094<br />
&nbsp;<strong>mode lacp&nbsp;&nbsp; //</strong><strong>聚合协议为LACP</strong><br />
#<br />
interface GigabitEthernet0/0/1<br />
&nbsp;eth-trunk 22<br />
#<br />
interface GigabitEthernet0/0/2<br />
&nbsp;eth-trunk 22<br />
#<br />
interface GigabitEthernet0/0/3<br />
&nbsp;eth-trunk 22<br />
#<br />
interface GigabitEthernet0/0/4<br />
&nbsp;eth-trunk 22<br />
#</p>

<p>Catalyst 3560关于链路聚合的配置如下：</p>

<p>!<br />
interface FastEthernet0/1<br />
&nbsp;<strong>channel-protocol pagp&nbsp;&nbsp; //</strong><strong>聚合协议为PAGP</strong><br />
&nbsp;<strong>channel-group 22 mode desirable</strong><br />
&nbsp;switchport trunk encapsulation dot1q<br />
&nbsp;switchport mode trunk<br />
!<br />
interface FastEthernet0/2<br />
&nbsp;<strong>channel-protocol pagp</strong><br />
<strong>&nbsp;channel-group 22 mode desirable</strong><br />
&nbsp;switchport trunk encapsulation dot1q<br />
&nbsp;switchport mode trunk<br />
!<br />
interface FastEthernet0/3<br />
&nbsp;<strong>channel-protocol pagp</strong><br />
<strong>&nbsp;channel-group 22 mode desirable</strong><br />
&nbsp;switchport trunk encapsulation dot1q<br />
&nbsp;switchport mode trunk<br />
!<br />
interface FastEthernet0/4<br />
&nbsp;<strong>channel-protocol pagp</strong><br />
&nbsp;<strong>channel-group 22 mode desirable</strong><br />
&nbsp;switchport trunk encapsulation dot1q<br />
&nbsp;switchport mode trunk<br />
&nbsp;!</p>
</div>

故障分析

<div id="content_3">
<p>S5700使用国际互联网组织制定的共有协议LACP建立链路聚合，且查看S5700配置后发现没有配置方面的错误。</p>

<p>而Cisco在链路聚合上除LACP协议外，还支持其私有的PAGP协议。在查看Catalyst 3560的配置后，发现使用的是其私有PAGP协议，而非LACP协议。因此导致两端的链路聚合无法形成。</p>
</div>

处理过程

<div id="content_4">
<p>由两端配置信息得出结论，该故障并非S5700导致，而是对端设备上配置错误。</p>

<p>告知用户该故障并非华为设备引起，请咨询Cisco相关单位寻求解决方案。</p>

<p>客户将对端Catalyst 3560使用的PAGP协议修改成LACP后，故障解决。</p>

<p>更改为LACP协议后的Catalyst3560关于Eth-Trunk方面的配置如下：</p>

<p>!<br />
interface FastEthernet0/1<br />
&nbsp;<strong>channel-protocol lacp&nbsp;&nbsp; //</strong><strong>聚合协议为LACP</strong><strong>模式</strong><br />
<strong>&nbsp;channel-group 22 mode active&nbsp;&nbsp; //</strong><strong>模式为active</strong><br />
&nbsp;switchport trunk encapsulation dot1q<br />
&nbsp;switchport mode trunk<br />
!<br />
interface FastEthernet0/2<br />
&nbsp;<strong>channel-protocol lacp&nbsp;&nbsp;&nbsp; </strong>&nbsp;<br />
<strong>&nbsp;channel-group 22 mode active&nbsp;&nbsp;&nbsp; </strong>&nbsp;<br />
&nbsp;switchport trunk encapsulation dot1q<br />
&nbsp;switchport mode trunk<br />
!<br />
interface FastEthernet0/3<br />
&nbsp;<strong>channel-protocol lacp</strong><br />
<strong>&nbsp;channel-group 22 mode active</strong><br />
&nbsp;switchport trunk encapsulation dot1q<br />
&nbsp;switchport mode trunk<br />
!<br />
interface FastEthernet0/4<br />
&nbsp;<strong>channel-protocol lacp</strong><br />
<strong>&nbsp;channel-group 22 mode active</strong><br />
&nbsp;switchport trunk encapsulation dot1q<br />
&nbsp;switchport mode trunk<br />
&nbsp;!</p>
</div>

建议/总结

在跨厂商建立对接时，一定要注意两端设备各自所使用的协议。