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Cisco Systems IntelligentGigabit Ethernet Switch Modules for the IBMBladeCenter, Software Configuration Guide
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Chapter22 Configuring Network Security with ACLs
Applying ACLs to Terminal Lines or Physical Interfaces

Creating MAC Access Groups

Beginning in privileged EXEC mode, follow these steps to create MAC access groups and to apply a
MAC access list to an interface:
This example shows how to apply ACL 2 on an interface to filter packets entering the interface:
Switch(config)# interface gigabitethernet0/17
Router(config-if)# mac access-group 2 in
Note The mac access-group interface configuration command is only valid when applied to a Layer 2
interface.
For inbound ACLs, after receiving a packet, the switch checks the packet against the ACL. If the ACL
permits the packet, the switch continues to process the packet. If the ACL rejects the packet, the switch
discards the packet. The MAC ACL applies to both IP and non-IP packets.
When you apply an undefined ACL to an interface, the switch acts as if the ACL has not been applied
to the interface and permits all packets. Remember this behavior if you use undefined ACLs as a means
of network security.
Applying ACLs to Terminal Lines or Physical Interfaces
Note Before applying an ACL to a physical interface, see the “Guidelines for Applying ACLs to Physical
Interfaces” section on page22-5.
You can apply ACLs to any management interface. For information on creating ACLs on management
interfaces, see the “Configuring IP Services” section of the Cisco IOS IP and IP Routing Configuration
Guide, Cisco IOS Release 12.1 and the Cisco IOS IP and IP Routing Command Re ference, Cisco IOS
Release12.1.
Note The limitations that apply to ACLs on physical interfaces do not apply to ACLs on management
interfaces.
Command Purpose
Step1 configure terminal Enter global configuration mode.
Step2 interface interface-id Identify a specific interface for configuration, and enter interface
configuration mode.
The interface must be a Layer 2 interface.
Step3 mac access-group {name} {in} Control access to the specified interface by using the MAC access list name.
Step4 end Return to privileged EXEC mode.
Step5 show mac-access group Display the MAC ACLs applied on the switch.
Step6 copy running-config startup-config (Optional) Save your entries in the configuration file.