Creating A Vlan Map - Cisco Catalyst 3750-X Software Configuration Manual

Configuring VLAN Maps
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For configuration examples, see the
For information about using both router ACLs and VLAN maps, see the
Configuration Guidelines" section on page

Creating a VLAN Map

Each VLAN map consists of an ordered series of entries. Beginning in privileged EXEC mode, follow
these steps to create, add to, or delete a VLAN map entry:
Command
Step 1
configure terminal
vlan access-map name [number]
Step 2
action {drop | forward}
Step 3
Catalyst 3750-X and 3560-X Switch Software Configuration Guide
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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 up if you have configured a very large number of ACLs.
Logging is not supported for VLAN maps.
When a switch has an IP access list or MAC access list applied to a Layer 2 interface, and you apply
a VLAN map to a VLAN that the port belongs to, the port ACL takes precedence over the VLAN
map.
If VLAN map configuration cannot be applied in hardware, all packets in that VLAN must be
bridged and routed by software.
You can configure VLAN maps on primary and secondary VLANs. However, we recommend that
you configure the same VLAN maps on private-VLAN primary and secondary VLANs.
When a frame is Layer-2 forwarded within a private VLAN, the same VLAN map is applied at the
ingress side and at the e gress side. When a frame is routed from inside a private VLAN to an external
port, the private-VLAN map is applied at the ingress side.
For frames going upstream from a host port to a promiscuous port, the VLAN map configured
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on the secondary VLAN is applied.
For frames going downstream from a promiscuous port to a host port, the VLAN map
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configured on the primary VLAN is applied.
To filter out specific IP traffic for a private VLAN, you should apply the VLAN map to both the
primary and secondary VLANs. For more information about private VLANs, see
"Configuring Private VLANs."
Purpose
Enter global configuration mode.
Create a VLAN map, and give it a name and (optionally) a number. The
number is the sequence number of the entry within the map.
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.
Entering this command changes to access-map configuration mode.
(Optional) Set the action for the map entry. The default is to forward.
Chapter 37
"Using VLAN Maps in Your Network" section on page
37-38.
Configuring Network Security with ACLs
Chapter 18,
37-35.
"VLAN Maps and Router ACL
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