3Com 4500G Family Configuration Manual page 1053

[Device] mac-address information mode syslog
# Enable MAC Information on GigabitEthernet 1/0/1
[Device] interface gigabitethernet 1/0/1
[Device-GigabitEthernet1/0/1] mac-address information enable added
[Device-GigabitEthernet1/0/1] mac-address information enable deleted
[Device-GigabitEthernet1/0/1] quit
# Set the MAC Information queue length to 100.
[Device] mac-address information queue-length 100
# Set the interval for sending Syslog or Trap messages to 20 seconds.
[Device] mac-address information interval 20
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