Dell PowerSwitch S4820T 9.50.1 Configuration Guide for the S4820T System - Page 548

mac learning-limit mac-address-sticky Using sticky MAC addresses allows you to associate a specific port with MAC addresses from trusted devices. If you enable sticky MAC, the specified port retains any dynamically-learned addresses and prevents them from being transferred or learned on other ports. If you configure mac-learning-limit and you enabled sticky MAC, all dynamically-learned addresses are converted to sticky MAC addresses for the selected port. Any new MAC addresses learned on this port is converted to sticky MAC addresses. To save all sticky MAC addresses into a configuration file that can be used as a startup configuration file, use the write config command. If the number of existing MAC addresses is fewer than the configured mac learn limit, any additional MAC addresses are converted to sticky MACs on that interface. To remove all sticky MAC addresses from the running config file, disable sticky MAC and use the write config command. When you enable sticky mac on an interface, dynamically-learned MAC addresses do not age, even if you enabled mac-learning-limit dynamic. If you configured mac-learning-limit and maclearning-limit dynamic and you disabled sticky MAC, any dynamically-learned MAC addresses ages. mac learning-limit station-move The mac learning-limit station-move command is available on the S4820T platform. The station-move option, allows a MAC address already in the table to be learned off of another interface. For example, if you disconnect a network device from one interface and reconnect it to another interface, the MAC address is learned on the new interface. When the system detects this "station move," the system clears the entry learned on the original interface and installs a new entry on the new interface. mac learning-limit no-station-move The no-station-move option, also known as "sticky MAC," provides additional port security by preventing a station move. When you configure this option, the first entry in the table is maintained instead of creating an entry on the new interface. no-station-move is the default behavior. Entries created before you set this option are not affected. To display a list of all interfaces with a MAC learning limit, use the following command. Display a list of all interfaces with a MAC learning limit. EXEC Privilege mode show mac learning-limit Dell Networking OS Behavior: The systems do not generate a station-move violation log entry for physical interfaces or port-channels when you configure mac learning-limit or when you configure mac learning-limit station-move-violation log. Dell Networking OS detects a station-move violation only when you configure mac learning-limit dynamic and logs the violation only when you configure the mac learning-limit station-move-violation log, as shown in the following example. Dell(conf-if-gi-1/1)#show config ! interface GigabitEthernet 1/1 548 Layer 2