在2块HWIC-4ESW之间,一定要用一根网线连接起来，否则,VLAN无法使用，切记！

这次在一台上配备了两块HWIC-4ESW，开始时没有注意，根本没法用这两块以太网交换模块，搞得自己很紧张，以为碰到不良总代，出了O货，后来到官网上查了一下，原来还有这么一说，算是思科的一个小小硬伤吧，为什么不在机框总线里把这个问题处理好，却一定要在外面飞线呢？

看来思科每次在嘲笑华为时，应该摸下自己的脸是否有点红了。

思科官方的文档：

Configuring Stacking Stacking is connection of two modules resident in same chassis so that they behave as a single . When a chassis is populated with two switch modules, the user must configure both of them to operate in stacked mode. This is done by selecting one port from each switch module and configuring it to be a stacking partner. The user must then connect with a cable the stacking partners from each switch module to physically stack the switch modules. Any one port in a switch module can be designated as the stacking partner for that switch module.

Beginning in privileged EXEC mode, follow these steps to configure a pair of ports on two different switch modules as stacking partners.

SUMMARY STEPS

1. interface fastethernet interface-id

2. no shutdown

3. switchport stacking-partner interface FastEthernet partner-interface-id

4. exit

5. interface fastethernet partner-interface-id

6. no shutdown

7. end

DETAILED STEPS

Command Purpose Step 1 Router(config)#interface fastethernetinterface-idSelects the interface to configure.

Step 2

Router(config-if)#no shutdownActivates the interface. (Required only if you shut down the interface.)

Step 3

Router(config-if)#switchportstacking-partner interface FastEthernetpartner-interface-idSelects and configures the stacking partner port.

Step 4

Router(config-if)#exitExits interface configuration mode.

Step 5

Router(config)#interface fastethernetpartner-interface-idSelects the stacking partner interface.

Step 6

Router(config-if)#no shutdownActivates the stacking partner interface.

Step 7

Router(config-if)#endExits configuration mode.