Cisco Catalyst 3750 Metro - Switchport Vlan Mapping

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Catalyst 3750 Metro Switch Command Reference
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Chapter 2 Catalyst 3750 Metro Switch Cisco IOS Commands
switchport vlan mapping
Command History
Usage Guidelines Use the switchport vlan mapping command only on ES ports that are attached to the service-provider
network.
VLAN mapping acts as a filter on the ES ports and does not affect the internal operation of the switch.
The VLAN ID in the 802.1Q tag is mapped just before a packet is sent or just after a packet is received
on the ES port.
The service-provider VLANs are not visible to the switch, so all configuration and statistics relate to the
customer-side VLANs. For example, an input access control list (ACL) on the ES port would be applied
to the customer-side VLAN after it is mapped from the service-provider-side VLAN.
To configure a one-to-one VLAN mapping, use the vlan-id translated-vlan-id keywords. To configure a
two-to-one VLAN mapping, use the dot1q-tunnel outer-vlan-id inner-vlan-id translated-vlan-id
keywords. To configure two-to-two VLAN mapping, use the internal dot1q-tunnel
internal-outer-vlan-id internal-inner-vlan-id external dot1q-tunnel external-outer-vlan-id
external-inner-vlan-id keywords.
You can use the switchport vlan mapping dot1q-tunnel command to translate the outer VLAN and the
inner VLAN in an 802.1Q tunnel to the service-provider VLAN. The switch can then translate
overlapping customer VLANs by encapsulating the customer traffic in 802.1Q tunnels. Use the drop
keyword to drop all VLAN traffic except traffic that is explicitly mapped.
When using the use the switchport vlan mapping internal dot1q-tunnel internal-outer-vlan-id
internal-inner-vlan-id external dot1q-tunnel external-outer-vlan-id external-inner-vlan-id command,
make sure that the inner VLAN ID of the original 802.1Q packet (internal-inner-vlan-id) and the inner
VLAN ID in the service-provide network (external-inner-vlan-id) match. All switch configurations and
actions, including QoS actions, apply to the 802.1Q inner and outer VLANs.
Examples This example shows how to configure an interface so that 802.1Q traffic with the outer VLAN ID 5 and
the inner VLAN ID 6 would leave the switch with the single VLAN ID 10 (a two-to-one mapping). The
802.1Q traffic with the outer VLAN 5 and any inner VLAN ID other than 6 would be dropped. Other
traffic on VLAN 5 would also be dropped.
Switch(config)# interface gigabitethernet1/1/2
Switch(config-if)# switchport vlan mapping dot1q-tunnel 5 6 10
Switch(config-if)# switchport vlan mapping dot1q-tunnel 5 drop
This example shows how to map the outer and inner VLAN IDs of the original 802.1Q packet to the outer
and inner VLAN IDs in the service-provider network (a two-to-two mapping).
Switch(config)# interface gigabitethernet1/1/1
Switch(config-if)# switchport vlan mapping internal dot1q-tunnel 5 6 external dot1q tunnel
15 6
Release Modification
12.1(14)AX This command was introduced.
12.2(25)EY The internal dot1q-tunnel internal-outer-vlan-id internal-inner-vlan-id
external dot1q-tunnel external-outer-vlan-id external-inner-vlan-id
keywords were added.