Related Documentation
- EX, M, MX, T Series
- Configuring PIM Provider Tunnels for an MBGP MVPN
- M, MX, T Series
- Example: Configuring Selective Provider Tunnels Using Wildcards
Example: Configuring a PIM-SSM Provider Tunnel for an MBGP MVPN
This example shows how to configure a PIM-SSM provider tunnel for an MBGP MVPN. The configuration enables service providers to carry customer data in the core. This example shows how to configure PIM-SSM tunnels as inclusive PMSI and uses the unicast routing preference as the metric for determining the single forwarder (instead of the default metric, which is the IP address from the global administrator field in the route-import community).
Requirements
Before you begin:
- Configure the router interfaces. See the Junos OS Network Interfaces Library for Routing Devices.
- Configure the BGP-to-OSPF routing policy. See the Routing Policy Feature Guide for Routing Devices.
Overview
When a PE receives a customer join or prune message from a CE, the message identifies a particular multicast flow as belonging either to a source-specific tree (S,G) or to a shared tree (*,G). If the route to the multicast source or RP is across the VPN backbone, then the PE needs to identify the upstream multicast hop (UMH) for the (S,G) or (*,G) flow. Normally the UMH is determined by the unicast route to the multicast source or RP.
However, in some cases, the CEs might be distributing to the PEs a special set of routes that are to be used exclusively for the purpose of upstream multicast hop selection using the route-import community. More than one route might be eligible, and the PE needs to elect a single forwarder from the eligible UMHs.
The default metric for the single forwarder election is the IP address from the global administrator field in the route-import community. You can configure a router to use the unicast route preference to determine the single forwarder election.
This example includes the following settings.
- provider-tunnel pim-ssm group-address—Specifies
a valid SSM VPN group address. The SSM VPN group address and the source
address are advertised by the type-1 autodiscovery route. On receiving
an autodiscovery route with the SSM VPN group address and the source
address, a PE router sends an (S,G) join in the provider space to
the PE advertising the autodiscovery route. All PE routers exchange
their PIM-SSM VPN group address to complete the inclusive provider
multicast service interface (I-PMSI). Unlike a PIM-ASM provider tunnel,
the PE routers can choose a different VPN group address because the
(S,G) joins are sent directly toward the source PE.
Note: Similar to a PIM-ASM provider tunnel, PIM must be configured in the default master instance.
- unicast-umh-election—Specifies that the PE router uses the unicast route preference to determine the single-forwarder election.
Figure 1 shows the topology used in this example.
Figure 1: PIM-SSM Provider Tunnel for an MBGP MVPN Topology

Configuration
CLI Quick Configuration
To quickly configure this example, copy the following commands, paste them into a text file, remove any line breaks, change any details necessary to match your network configuration, and then copy and paste the commands into the CLI at the [edit] hierarchy level.
Step-by-Step Procedure
The following example requires you to navigate various levels in the configuration hierarchy. For information about navigating the CLI, see Using the CLI Editor in Configuration Mode in the CLI User Guide.
To configure a PIM-SSM provider tunnel for an MBGP MVPN:
Configure the interfaces in the master routing instance on the PE routers. This example shows the interfaces for one PE router.
[edit interfaces]user@host# set fe-0/2/0 unit 0 family inet address 192.168.195.109/30user@host# set fe-0/2/1 unit 0 family inet address 192.168.195.5/27user@host# set fe-0/2/2 unit 0 family inet address 20.10.1.1/30user@host# set fe-0/2/2 unit 0 family isouser@host# set fe-0/2/2 unit 0 family mplsuser@host# set lo0 unit 1 family inet address 10.10.47.100/32user@host# set lo0 unit 2 family inet address 10.10.48.100/32Configure the autonomous system number in the global routing options. This is required in MBGP MVPNs.
[edit routing-options]user@host# set autonomous-system 100Configure the routing protocols in the master routing instance on the PE routers.
user@host# set protocols mpls interface all
[edit protocols bgp group ibgp]user@host# set type internaluser@host# set family inet-vpn anyuser@host# set family inet-mvpn signalinguser@host# set neighbor 10.255.112.155
[edit protocols isis]user@host# set level 1 disableuser@host# set interface alluser@host# set interface fxp0.0 disable
[edit protocols ospf]user@host# set traffic-engineeringuser@host# set area 0.0.0.0 interface alluser@host# set area 0.0.0.0 interface fxp0.0 disable
user@host# set protocols ldp interface all
[edit protocols pim]user@host# set rp static address 10.255.112.155user@host# set interface all mode sparse-denseuser@host# set interface all version 2user@host# set interface fxp0.0 disableConfigure routing instance VPN-A.
[edit routing-instances VPN-A]user@host# set instance-type vrfuser@host# set interface fe-0/2/1.0user@host# set interface lo0.1user@host# set route-distinguisher 10.255.112.199:100user@host# set provider-tunnel pim-ssm group-address 232.1.1.1user@host# set vrf-target target:100:100user@host# set vrf-table-labeluser@host# set routing-options auto-exportuser@host# set protocols ospf export bgp-to-ospfuser@host# set protocols ospf area 0.0.0.0 interface lo0.1user@host# set protocols ospf area 0.0.0.0 interface fe-0/2/1.0user@host# set protocols pim rp static address 10.10.47.101user@host# set protocols pim interface lo0.1 mode sparse-denseuser@host# set protocols pim interface lo0.1 version 2user@host# set protocols pim interface fe-0/2/1.0 mode sparse-denseuser@host# set protocols pim interface fe-0/2/1.0 version 2user@host# set protocols mvpnConfigure routing instance VPN-B.
[edit routing-instances VPN-B]user@host# set instance-type vrfuser@host# set interface fe-0/2/0.0user@host# set interface lo0.2user@host# set route-distinguisher 10.255.112.199:200user@host# set provider-tunnel pim-ssm group-address 232.2.2.2user@host# set vrf-target target:200:200user@host# set vrf-table-labeluser@host# set routing-options auto-exportuser@host# set protocols ospf export bgp-to-ospfuser@host# set protocols ospf area 0.0.0.0 interface lo0.2user@host# set protocols ospf area 0.0.0.0 interface fe-0/2/0.0user@host# set protocols pim rp static address 10.10.48.101user@host# set protocols pim interface lo0.2 mode sparse-denseuser@host# set protocols pim interface lo0.2 version 2user@host# set protocols pim interface fe-0/2/0.0 mode sparse-denseuser@host# set protocols pim interface fe-0/2/0.0 version 2user@host# set protocols mvpnConfigure the topology such that the BGP route to the source advertised by PE1 has a higher preference than the BGP route to the source advertised by PE2.
[edit protocols bgp]user@host# set group ibgp local-preference 120Configure a higher primary loopback address on PE2 than on PE1. This ensures that PE2 is the MBGP MVPN single-forwarder election winner.
[edit]user@host# set interface lo0 unit 1 family inet address 1.1.1.1/32 primaryConfigure the unicast-umh-knob statement on PE3.
[edit]user@host# set routing-instances VPN-A protocols mvpn unicast-umh-electionuser@host# set routing-instances VPN-B protocols mvpn unicast-umh-electionIf you are done configuring the device, commit the configuration.
user@host# commit
Results
Confirm your configuration by entering the show interfaces, show protocols, show routing-instances, and show routing-options commands from configuration mode. If the output does not display the intended configuration, repeat the instructions in this example to correct the configuration.
Verification
To verify the configuration, start the receivers and the source. PE3 should create type-7 customer multicast routes from the local joins. Verify the source-tree customer multicast entries on all PE routers. PE3 should choose PE1 as the upstream PE toward the source. PE1 receives the customer multicast route from the egress PEs and forwards data on the PSMI to PE3.
To confirm the configuration, run the following commands:
- show route table VPN-A.mvpn.0 extensive
- show multicast route extensive instance VPN-A
Related Documentation
- EX, M, MX, T Series
- Configuring PIM Provider Tunnels for an MBGP MVPN
- M, MX, T Series
- Example: Configuring Selective Provider Tunnels Using Wildcards
Published: 2013-07-31
Related Documentation
- EX, M, MX, T Series
- Configuring PIM Provider Tunnels for an MBGP MVPN
- M, MX, T Series
- Example: Configuring Selective Provider Tunnels Using Wildcards