PLANET XGS3-24040 - Manual (Page 138)

Chapter 15 MAC Table Configuration
15-5
15.4 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.
15.5 MAC Address Function Extension
15.5.1 MAC Address Binding
15.5.1.1 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 stream destined for the other MAC addresses that not bound to the port will not be allowed
to pass through the port.
15.5.1.2 MAC Address Binding Configuration Task List
1. Enable MAC address binding function for the ports
2. Lock the MAC addresses for a port
3. MAC address binding property configuration
1. Enable MAC address binding function for the ports
Command Explanation
Port Mode