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Software Configuration Guide—Release 12.2(25)SG
OL-7659-03
Chapter33 Configuring Network Securi ty with ACLs
Configuring VLAN Maps
Note You cannot apply a VLAN map to a VLAN on a switch that has ACLs applied to Layer 2 interfaces (port
ACLs).
VLAN Map Configuration Guidelines
Keep the following guidelines in mind when configuring VLAN maps:
•VLAN maps do not filter IPv4 ARP packets.
•If there is no router ACL configured to deny traffic on a routed VLAN interface (input or output),
and no VLAN map configured, all traffic is permitted.
•Each VLAN map consists of a series of entries. The order of entries in a VLAN map is important .
A packet that comes into the switch is tested against the first entry in the VLAN map. If it matches,
the action specified for that part of the VLAN map is taken. If there is no match, the packet is tested
against the next entry in the map.
•If the VLAN map has at least one match clause for the type of packet (IP or MAC) and the packet
does not match any of these match clauses, the default is to drop the packet. If there is no match
clause for that type of packet in the VLAN map, the default is to forward the packet.
•The system might take longer to boot if you have configured a very large number of ACLs.
Creating and Deleting VLAN Maps
Each VLAN map consists of an ordered series of entries. To create, add to, or delete a VLAN map entry,
perform this task:
Command Purpose
Step1 Switch# configure terminal Enters global configuration mode.
Step2 Switch(config)# vlan access-map
name
[
number
]
Creates a VLAN map, and give it a name and (optionally) a number. The
number is the sequence number of the entry within the m ap.
When you create VLAN maps with the same name, numbers are assigned
sequentially in increments of 10. When modifying or deleting maps, you
can enter the number of the map entry that you want to modify or delete.
This command enables access-map configuration mode.
Step3 Switch(config-access-map)# action
{drop | forward}
(Optional) Sets the action for the map entry. The default is to forward.
Step4 Switch(config-access-map)# match
{ip | mac} address {
name
|
number
}
[
name
|
number
]
Matches the packet (using either the IP or MAC address) against one or
more standard or extended access lists. Note that packets are matched only
against access lists of the correct protocol type. IP packets are compar ed
with standard or extended IP access lists. Non-IP packets are only compared
with named MAC extended access lists. If a match clause is not specified,
the action is taken on all packets.
Step5 Switch(config-access-map)# end Returns to global configuration mode.