Enterasys Networks Enterasys D2 D2G124-12P - Manual (Page 470)

Configuring MAC Locking
15-46 Security Configuration
Configuring MAC Locking
This feature locks a MAC address to one or more ports, preventing connection of unauthorized
devices through the port(s). When source MAC addresses are received on specified ports, the
switch discards all subsequent frames not containing the configured source addresses. The only
frames forwarded on a “locked” port are those with the “locked” MAC address(es) for that port.
There are two methods of locking a MAC to a port: first arrival and static. The first arrival method
is defined to be locking the first n number of MACs which arrive on a port configured with MAC
locking enabled. The value n is configured with the set maclock firstarrival command.
The static method is defined to be statically provisioning a MAC‐port lock using the set maclock
command. The maximum number of static MAC addresses allowed for MAC locking on a port
can be configured with the set maclock static command.
You can configure the switch to issue a violation trap if a packet arrives with a source MAC
address different from any of the currently locked MAC addresses for that port.
MACs are unlocked as a result of:
• A link down event
• When MAC locking is disabled on a port
• When a MAC is aged out of the forwarding database when FirstArrival aging is enabled
When properly configured, MAC locking is an excellent security tool as it prevents MAC spoofing
on configured ports. Also if a MAC were to be secured by something like Dragon Dynamic
Intrusion Detection, MAC locking would make it more difficult for a hacker to send packets into
the network because the hacker would have to change their MAC address and move to another
port. In the meantime the system administrator would be receiving a maclock trap notification.
Purpose
To review, disable, enable, and configure MAC locking.
Commands
authenticated mac
address If authentication has succeeded, displays the MAC address assigned for egress.
vlan id If authentication has succeeded, displays the assigned VLAN id for ingress.
Table 15-50 show vlanauthorization Output Details (Continued)
Output Field What It Displays...
For information about... Refer to page...
show maclock 15-47
show maclock stations 15-48
set maclock enable 15-49
set maclock disable 15-50
set maclock 15-50
clear maclock 15-51