Specifying the endpoint of a vpls instance, Special considerations for dual-tagged endpoints – Brocade Multi-Service IronWare Multiprotocol Label Switch (MPLS) Configuration Guide (Supporting R05.6.00) User Manual
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Multi-Service IronWare Multiprotocol Label Switch (MPLS) Configuration Guide
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show mpls vpls detail
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Specifying the endpoint of a VPLS instance
When the user configures the VPLS endpoint, the user specifies what happens to packets exiting
the VPLS instance, which VLAN the packet belongs to, as well as whether it is transmitted from the
PE device to the CE device over a dual-tagged, single-tagged, or untagged port. The user can also
specify a server Link Aggregation Group (LAG) group as the endpoint of a VPLS instance.
A VPLS instance can be configured between any combination of dual-tagged, single-tagged, and
untagged endpoints. For dual-tagged ports, traffic flows between the dual-tagged endpoint and the
MPLS cloud are also supported for traffic switched between a local endpoint and remote peers.
NOTE
Unless VPLS tagged mode is enabled, VPLS operates in raw mode, meaning no VLAN tags are
carried across the MPLS cloud to remote peers. For more information, see
.
The Customer Edge (CE) device is connected to the PE router over one or more dual-tagged,
single-tagged, or tagged ports.
•
With a single-tagged port, each pair (port, VLAN ID) is identified as a unique endpoint. When
VPLS raw mode is in effect, the tag is of significance between the CE and the PE and is not sent
across the MPLS cloud. When VPLS tagged mode is enabled, the tag is sent across the MPLS
cloud.
•
In the case of an untagged port, an endpoint is identified by the physical port alone, and the
packets are sent in untagged Ethernet format within the MPLS payload.
•
In the case of a dual-tagged port, the packets contain both an outer VLAN tag and an inner
VLAN tag. In this configuration, an endpoint can receive packets with two tags and forward
them to the other endpoint either single-tagged or dual-tagged. When VPLS tagged mode is
enabled, the inner VLAN tag is sent across the MPLS cloud.
All VPLS endpoints can be dual mode ports (tagged-untagged). An untagged endpoint port is
removed from the default VLAN ID 1 and cannot be added back to the default VLAN. A VPLS
endpoint can be tagged in multiple VPLS and Layer 2 VLANs and untagged in one other VLAN.
Special considerations for dual-tagged endpoints
Before configuring a dual-tagged VPLS endpoint, consider the following:
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The tag protocol identifier (TPID) of the inner VLAN tag must be 0x8100 be classified as
dual-tagged and recognized by dual-tagged endpoints. When the TPID is not 0x8100, the
packet is classified as a single-tagged packet.
•
The TPID of the outer VLAN tag must be the port’s configured tag type (the default tag type is
0x8100).
•
The System Max value for the Internal Forwarding Lookup (IFL) CAM partition must not be set
to 0 (zero). When it is set to zero, an informational message such as the following is displayed.
Brocade(config-mpls)# vpls test 10
Brocade(config-mpls-vpls-test10)# vlan 100 inner-vlan 200
Brocade(config-mpls-vpls-test_10-vlan-100-inner-vlan-200)# tagged Ethernet2/1