Example: Configuring a Provider Bridge Network with Normalized
VLAN Tags
This topic provides a configuration example to
help you effectively configure a network of Juniper Networks MX Series
3D Universal Edge Routers for a bridge domain or virtual private LAN
service (VPLS) environment. The emphasis here is on choosing the normalized
virtual LAN (VLAN) configuration. The VPLS configuration is not covered
in this chapter. For more information about configuring Ethernet pseudowires
as part of VPLS, see the Junos OS Feature Guides.
 | Note:
This topic does not present exhaustive configuration
listings for all routers in the figures. However, you can use it with
a broader configuration strategy to complete the MX Series router
network configurations. |
Consider the provider bridge network shown in Figure 1.
Figure 1: Provider Bridge
Network Using Normalized VLAN Tags
The Layer 2 provider edge (PE) routers are MX Series routers.
Each site is connected to two provider (P) routers for redundancy,
although both links are only shown for L2-PE1 at Site 1. Site 1 is
connected to P0 and P1 (as shown), Site 2 is connected to P0 and P2
(not shown), Site 3 is connected to P2 and P3 (as shown), and Site
4 is connected to P1 and P3 (as shown). VPLS pseudowires configured
on the PE and P routers carry traffic between the sites.
The VLANs’ bridging paths are shown with distinct
dashed and dotted lines. The VLANs at each site are:
- L2-PE1 at Site 1: VLAN 100 and VLAN 300
- L2-PE2 at Site 2: VLAN 100
- L2-PE3 at Site 3: VLAN 100
- L2-PE4 at Site 4: VLAN 300
 | Note:
The configurations in this chapter are only
partial examples of complete and functional router configurations.
Do not copy these configurations and use them directly on an actual
system. |
The following is the configuration of interfaces, virtual
switches, and bridge domains for MX Series router L2-PE1:
[edit]interfaces ge-1/0/0 {encapsulation flexible-ethernet-services;flexible-vlan-tagging;unit 1 {encapsulation vlan-bridge;vlan-id 100;}unit 11 {encapsulation vlan-bridge;vlan-id 301;}}
interface ge-2/0/0 {encapsulation flexible-ethernet-services;flexible-vlan-tagging;unit 1 {encapsulation vlan-bridge;vlan-id 100;}}
interface ge-3/0/0 {encapsulation flexible-ethernet-services;flexible-vlan-tagging;unit 1 {encapsulation vlan-bridge;vlan-id 200; # NOTE: 200 is translated to normalized VLAN
value}}
interfaces ge-4/0/0 {encapsulation flexible-ethernet-services;flexible-vlan-tagging;unit 1 {encapsulation vlan-bridge;vlan-tags outer 500 inner 100; # This places two VLAN tags
on the provider #
pseudowire}}
interfaces ge-5/0/0 {encapsulation flexible-ethernet-services;flexible-vlan-tagging;unit 1 {encapsulation vlan-bridge;vlan-tags outer 500 inner 100; # This places two VLAN tags
on the provider #
pseudowire}unit 11 {encapsulation vlan-bridge;vlan-tags outer 600 inner 300; # This places two VLAN tags
on the provider #
pseudowire}}
interfaces ge-6/0/0 {encapsulation flexible-ethernet-services;flexible-vlan-tagging;unit 11 {encapsulation vlan-bridge;vlan-id 300;}}
routing-instances {customer-c1-virtual-switch {instance-type virtual-switch ;bridge-domains {c1-vlan-100 {domain-type bridge;vlan-id 100; # Customer VLAN 100 uses these five logical
interfacesinterface ge-1/0/0.1;interface ge-2/0/0.1;interface ge-3/0/0.1;interface ge-4/0/0.1;interface ge-5/0/0.1;} # End of c1-vlan-100} # End of bridge-domains} # End of customer-c1-virtual-switchcustomer-c2-virtual-switch {instance-type virtual-switch ;bridge-domains {c2-vlan-300 {domain-type bridge;vlan-id 300; # Customer VLAN 300 uses these three logical
interfacesinterface ge-1/0/0.11;interface ge-5/0/0.11;interface ge-6/0/0.11;} # End of c1-vlan-300} # End of bridge-domains} # End of customer-c2-virtual-switch} # end of routing-instances
Bridge domain c1–vlan-100 for customer-c1–virtual-switch has five logical interfaces:
- Logical interface ge-1/0/0.1 configured on physical
port ge-1/0/0.
- Logical interface ge-2/0/0.1 configured on physical
port ge-2/0/0.
- Logical interface ge-3/0/0.1 configured on physical
port ge-3/0/0.
- Logical interface ge-4/0/0.1 can exist on an
extended port/subinterface defined by the pair ge-4/0/0 and outer-vlan-tag 500.
- Logical interface ge-5/0/0.1 can exist on an
extended port/subinterface defined by the pair ge-5/0/0 and outer-vlan-tag 500.
The association of the received packet to a logical interface
is done by matching the VLAN tags of the received packet with the
VLAN tags configured on one of the logical interfaces on that physical
port. The vlan-id 100 configuration within the bridge domain c1–vlan-100 sets the normalized VLAN value to 100.
The following happens as a result of this configuration:
- Packets received on logical interfaces ge-1/0/0.1 or ge-2/0/0.1 with a single VLAN tag of 100 in the frame
are accepted.
- Packets received on logical interface ge-3/0/0.1 with a single VLAN tag of 200 in the frame are accepted and have
their tag values translated to the normalized VLAN tag value of 100.
- Packets received on logical interfaces ge-4/0/0.1 and ge-5/0/0.1 with outer tag values of 500 and inner tag
values of 100 are accepted.
- Unknown source MAC addresses and unknown destination MAC
addresses are learned based on their normalized VLAN values of 100
or 300.
- All packets sent on a logical interface always have their
associated vlan-id value(s) in their VLAN tag fields.
Configuration and function of bridge domain c2-vlan-300 for customer-c2-virtual-switch is similar to, but not identical
to, that of bridge domain c1-vlan-100 for customer-c1-virtual-switch.
Published: 2013-02-13