Examples Of Acls And Vlan Maps - Cisco WS-C3560-48PS-S Software Configuration Manual

Chapter 27 Configuring Network Security with ACLs
VLAN maps do not use the specific permit or deny keywords. To deny a packet by using VLAN maps,
create an ACL that would match the packet, and set the action to drop. A permit in the ACL counts as a
match. A deny in the ACL means no match.

Examples of ACLs and VLAN Maps

These examples show how to create ACLs and VLAN maps that for specific purposes.
Example 1
This example shows how to create an ACL and a VLAN map to deny a packet. In the first map, any
packets that match the ip1 ACL (TCP packets) would be dropped. You first create the ip1ACL to permit
any TCP packet and no other packets. Because there is a match clause for IP packets in the VLAN map,
the default action is to drop any IP packet that does not match any of the match clauses.
Switch(config)# ip access-list extended ip1
Switch(config-ext-nacl)# permit tcp any any
Switch(config-ext-nacl)# exit
Switch(config)# vlan access-map map_1 10
Switch(config-access-map)# match ip address ip1
Switch(config-access-map)# action drop
This example shows how to create a VLAN map to permit a packet. ACL ip2 permits UDP packets and
any packets that match the ip2 ACL are forwarded. In this map, any IP packets that did not match any of
the previous ACLs (that is, packets that are not TCP packets or UDP packets) would get dropped.
Switch(config)# ip access-list extended ip2
Switch(config-ext-nacl)# permit udp any any
Switch(config-ext-nacl)# exit
Switch(config)# vlan access-map map_1 20
Switch(config-access-map)# match ip address ip2
Switch(config-access-map)# action forward
Example 2
In this example, the VLAN map has a default action of drop for IP packets and a default action of forward
for MAC packets. Used with standard ACL 101 and extended named access lists igmp-match and
tcp-match, the map will have the following results:
•
•
•
•
•
Switch(config)# access-list 101 permit udp any any
Switch(config)# ip access-list extended igmp-match
Switch(config-ext-nacl)# permit igmp any any
Switch(config)# ip access-list extended tcp-match
Switch(config-ext-nacl)# permit tcp any any
Switch(config-ext-nacl)# exit
Switch(config)# vlan access-map drop-ip-default 10
Switch(config-access-map)# match ip address 101
Switch(config-access-map)# action forward
Switch(config-access-map)# exit
Switch(config)# vlan access-map drop-ip-default 20
Switch(config-access-map)# match ip address igmp-match
78-16156-01
Forward all UDP packets
Drop all IGMP packets
Forward all TCP packets
Drop all other IP packets
Forward all non-IP packets
Catalyst 3560 Switch Software Configuration Guide
Configuring VLAN Maps
27-31