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MAC Table Configuration
174
The configuration steps are listed below:
1. Set the MAC address 00-01-11-11-11-11 of PC1 as a filter address.
Switch(config)#mac-address-table static 00-01-11-11-11-11 discard vlan 1.
2.Set the static mapping relationship for PC2 and PC3 to port 1/0/7 and port 1/0/9,
respectively.
Switch(config)#mac-address-table static address 00-01-22-22-22-22 vlan 1 interface
ethernet 1/0/7
Switch(config)#mac-address-table static address 00-01-33-33-33-33 vlan 1 interface
ethernet 1/0/9
18.4
MAC Table Troubleshooting
Using the show mac-address-table command, a port is found to be failed to learn the
MAC of a device connected to it. Possible reasons:
The connected cable is broken.
Spanning Tree is enabled and the port is in ―discarding‖ status; or the device is
just connected to the port and Spanning Tree is still under calculation, wait until
the Spanning Tree calculation finishes, and the port will learn the MAC address.
If not the problems mentioned above, please check for the switch portand
contact technical support for solution.
18.5
MAC Address Function Extension
18.5.1
MAC Address Binding
18.5.1.1
Introduction to MAC Address Binding
Most switches support MAC address learning, each port can dynamically learn
several MAC addresses, so that forwarding data streams between known MAC addresses
within the ports can be achieved. If a MAC address is aged, the packet destined for that
entry will be broadcasted. In other words, a MAC address learned in a port will be used for
forwarding in that port, if the connection is changed to another port, the switch will learn
the MAC address again to forward data in the new port.
However, in some cases, security or management policy may require MAC
addresses to be bound with the ports, only data stream from the binding MAC are allowed
to be forwarded in the ports. That is to say, after a MAC address is bound to a port, only
the data stream destined for that MAC address can flow in from the binding port, data