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Table of Contents Expand all

play_arrow Overview
- Understanding Multitopology Routing
- Standards for Multitopology Routing
play_arrow Configuring Multitopology Routing
play_arrow Monitoring Multitopology Routing
- Example: Tracing Global Routing Protocol Operations
play_arrow Troubleshooting Network Issues
play_arrow Configuration Statements and Operational Commands
- Junos CLI Reference Overview
play_arrow Knowledge Base
- https://kb.juniper.net/

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English

Example: Configuring Multitopology Routing to Provide Redundancy for Multicast Traffic over Separate Network Paths

date_range 24-Nov-23

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This example shows how to use multitopology routing (MTR) to provide redundancy for multicast traffic over separate network paths. That is, two multicast sources send the same multicast stream, yet for redundancy purposes in the case of link failure, the two streams use disjoint paths.

Note:

Note there is no standard defined at this time for using MTR extensions to PIM.

Requirements

This example requires that Junos OS Release 9.0 or later is running on the provider core devices.

Overview

Assume that each source providing redundant multicast streams, S1 and S2, have different IP subnet addresses. Each source sends multicast traffic using different groups: G1 and G2. Further, assume that S1 and S2 are attached to the same customer edge (CE) device and use BGP to announce routes to the provider edge (PE) router.

For a complete set of configurations for all of the devices in the topology, see CLI Quick Configuration. The remainder of the example focuses on Device CE1 and Device PE1.

Figure 1 shows the sample topology.

Figure 1: Multitopology OSPF and BGP for Designating Links Belonging to Voice and Video Services

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.

Device CE1

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set interfaces fe-0/1/0 fastether-options loopback 
set interfaces fe-0/1/0 unit 0 family inet address 11.19.130.1/24 
set interfaces fe-0/1/0 unit 0 family inet address 11.19.131.1/24 
set interfaces fe-0/1/0 unit 0 family inet address 11.19.132.1/24
set interfaces ge-1/2/0 unit 1 description to-PE1
set interfaces ge-1/2/0 unit 1 family inet address 10.0.0.1/30
set interfaces lo0 unit 97 family inet address 10.255.165.97/32 primary
set protocols bgp group ebgp type external
set protocols bgp group ebgp local-address 10.0.0.1
set protocols bgp group ebgp family inet unicast
set protocols bgp group ebgp family inet multicast
set protocols bgp group ebgp export set_community
set protocols bgp group ebgp export inject_directs
set protocols bgp group ebgp peer-as 100
set protocols bgp group ebgp neighbor 10.0.0.2
set protocols pim interface fe-0/1/0.0 mode sparse
set protocols pim interface ge-1/2/0.1 mode sparse
set policy-options policy-statement inject_directs term a from protocol direct
set policy-options policy-statement inject_directs term a from interface fe-0/1/0.0
set policy-options policy-statement inject_directs term a then next policy
set policy-options policy-statement inject_directs term a then accept
set policy-options policy-statement inject_directs term b then reject
set policy-options policy-statement set_community term a from route-filter 11.19.130.0/24 exact
set policy-options policy-statement set_community term a from route-filter 11.19.131.0/24 exact
set policy-options policy-statement set_community term a then community add red
set policy-options policy-statement set_community term a then accept
set policy-options policy-statement set_community term b from route-filter 11.19.132.0/24 exact
set policy-options policy-statement set_community term b from route-filter 11.19.133.0/24 exact
set policy-options policy-statement set_community term b then community add blue
set policy-options policy-statement set_community term b then accept
set policy-options policy-statement set_community term default then accept
set policy-options community blue members target:50:50
set policy-options community red members target:40:40
set routing-options interface-routes rib-group inet if-rib
set routing-options static route 10.0.0.0/16 next-hop 10.0.0.2
set routing-options rib-groups inet.2 import-rib inet.0
set routing-options rib-groups if-rib import-rib inet.0
set routing-options rib-groups if-rib import-rib inet.2
set routing-options rib-groups if-rib import-policy inject_directs
set routing-options autonomous-system 101

Device CE2

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set interfaces fe-0/1/1 unit 0
set interfaces ge-1/2/0 unit 46 description to-PE2
set interfaces ge-1/2/0 unit 46 family inet address 10.0.0.46/30
set interfaces lo0 unit 20 family inet address 10.255.165.20/32 primary
set protocols bgp group ebgp type external
set protocols bgp group ebgp local-address 10.0.0.46
set protocols bgp group ebgp peer-as 100
set protocols bgp group ebgp neighbor 10.0.0.45
set routing-options autonomous-system 102

Device PE1

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set interfaces ge-1/2/0 unit 2 description to-CE1
set interfaces ge-1/2/0 unit 2 family inet address 10.0.0.2/30
set interfaces ge-1/2/1 unit 6 description to-P1
set interfaces ge-1/2/1 unit 6 family inet address 10.0.0.6/30
set interfaces ge-1/2/2 unit 9 description to-P3
set interfaces ge-1/2/2 unit 9 family inet address 10.0.0.9/30
set interfaces lo0 unit 93 family inet address 10.255.165.93/32 primary
set interfaces lo0 unit 93 family inet address 1.1.1.30/32
set interfaces lo0 unit 93 family inet address 2.2.2.30/32
set protocols bgp group ibgp type internal
set protocols bgp group ibgp local-address 10.255.165.93
set protocols bgp group ibgp family inet unicast
set protocols bgp group ibgp family inet multicast
set protocols bgp group ibgp export nhs_test
set protocols bgp group ibgp export nhs_inet0_self
set protocols bgp group ibgp neighbor 10.255.165.111
set protocols bgp group ibgp neighbor 10.255.165.203
set protocols bgp group ibgp neighbor 10.255.165.113
set protocols bgp group ibgp neighbor 10.255.165.95
set protocols bgp group ibgp neighbor 10.255.165.99
set protocols bgp group ebgp type external
set protocols bgp group ebgp local-address 10.0.0.2
set protocols bgp group ebgp family inet unicast
set protocols bgp group ebgp family inet multicast
set protocols bgp group ebgp peer-as 101
set protocols bgp group ebgp neighbor 10.0.0.1
set protocols ospf topology red topology-id 126
set protocols ospf topology blue topology-id 52
set protocols ospf area 0.0.0.0 interface ge-1/2/1.6 metric 10
set protocols ospf area 0.0.0.0 interface ge-1/2/1.6 topology blue metric 1
set protocols ospf area 0.0.0.0 interface ge-1/2/1.6 topology red
set protocols ospf area 0.0.0.0 interface ge-1/2/2.9 metric 10
set protocols ospf area 0.0.0.0 interface ge-1/2/2.9 topology red metric 1
set protocols ospf area 0.0.0.0 interface ge-1/2/2.9 topology blue
set protocols ospf area 0.0.0.0 interface lo0.93 passive
set protocols ospf area 0.0.0.0 interface 1.1.1.30 topology red
set protocols ospf area 0.0.0.0 interface 1.1.1.30 topology blue disable
set protocols ospf area 0.0.0.0 interface 2.2.2.30 topology blue
set protocols ospf area 0.0.0.0 interface 2.2.2.30 topology red disable
set protocols pim rib-group inet mcast-rib
set protocols pim interface ge-1/2/0.2 mode sparse
set protocols pim interface ge-1/2/1.6 mode sparse
set protocols pim interface ge-1/2/2.9 mode sparse
set policy-options policy-statement nhs_inet0_self term a from protocol bgp
set policy-options policy-statement nhs_inet0_self term a from rib inet.0
set policy-options policy-statement nhs_inet0_self term a then next-hop self
set policy-options policy-statement nhs_test term a from protocol bgp
set policy-options policy-statement nhs_test term a from community red
set policy-options policy-statement nhs_test term a then next-hop 1.1.1.30
set policy-options policy-statement nhs_test term a then next policy
set policy-options policy-statement nhs_test term a then accept
set policy-options policy-statement nhs_test term b from protocol bgp
set policy-options policy-statement nhs_test term b from community blue
set policy-options policy-statement nhs_test term b then next-hop 2.2.2.30
set policy-options policy-statement nhs_test term b then next policy
set policy-options policy-statement nhs_test term b then accept
set policy-options policy-statement nhs_test term c then next-hop self
set policy-options community blue members target:50:50
set policy-options community red members target:40:40
set routing-options rib-groups mcast-rib import-rib inet.2
set routing-options autonomous-system 100
set routing-options resolution rib inet.2 resolution-ribs :red.inet.0
set routing-options resolution rib inet.2 resolution-ribs :blue.inet.0
set routing-options topologies family inet topology red
set routing-options topologies family inet topology blue

Device PE2

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set interfaces ge-1/2/0 unit 38 description to-P2
set interfaces ge-1/2/0 unit 38 family inet address 10.0.0.38/30
set interfaces ge-1/2/1 unit 42 description to-P4
set interfaces ge-1/2/1 unit 42 family inet address 10.0.0.42/30
set interfaces ge-1/2/2 unit 45 description to-CE2
set interfaces ge-1/2/2 unit 45 family inet address 10.0.0.45/30
set interfaces lo0 unit 203 family inet address 10.255.165.203/32 primary
set interfaces lo0 unit 203 family inet address 1.1.1.40/32
set interfaces lo0 unit 203 family inet address 2.2.2.40/32
set protocols bgp group ibgp type internal
set protocols bgp group ibgp local-address 10.255.165.203
set protocols bgp group ibgp family inet unicast
set protocols bgp group ibgp family inet multicast
set protocols bgp group ibgp export nhs_test
set protocols bgp group ibgp export nhs_inet0_self
set protocols bgp group ibgp neighbor 10.255.165.111
set protocols bgp group ibgp neighbor 10.255.165.93
set protocols bgp group ibgp neighbor 10.255.165.113
set protocols bgp group ibgp neighbor 10.255.165.95
set protocols bgp group ibgp neighbor 10.255.165.99
set protocols bgp group ebgp type external
set protocols bgp group ebgp local-address 10.0.0.45
set protocols bgp group ebgp family inet unicast
set protocols bgp group ebgp family inet multicast
set protocols bgp group ebgp peer-as 102
set protocols bgp group ebgp neighbor 10.0.0.46
set protocols ospf topology red topology-id 126
set protocols ospf topology blue topology-id 52
set protocols ospf area 0.0.0.0 interface ge-1/2/0.38 metric 10
set protocols ospf area 0.0.0.0 interface ge-1/2/0.38 topology blue metric 1
set protocols ospf area 0.0.0.0 interface ge-1/2/0.38 topology red
set protocols ospf area 0.0.0.0 interface ge-1/2/1.42 metric 10
set protocols ospf area 0.0.0.0 interface ge-1/2/1.42 topology red metric 1
set protocols ospf area 0.0.0.0 interface ge-1/2/1.42 topology blue
set protocols ospf area 0.0.0.0 interface lo0.203 passive
set protocols ospf area 0.0.0.0 interface 1.1.1.40 topology red
set protocols ospf area 0.0.0.0 interface 1.1.1.40 topology blue disable
set protocols ospf area 0.0.0.0 interface 2.2.2.40 topology red disable
set protocols ospf area 0.0.0.0 interface 2.2.2.40 topology blue
set protocols pim rib-group inet mcast-rib
set protocols pim interface ge-1/2/0.38 mode sparse
set protocols pim interface ge-1/2/1.42 mode sparse
set protocols pim interface ge-1/2/2.45 mode sparse
set policy-options policy-statement nhs then next-hop self
set policy-options policy-statement nhs_inet0_self term a from protocol bgp
set policy-options policy-statement nhs_inet0_self term a from rib inet.0
set policy-options policy-statement nhs_inet0_self term a then next-hop self
set policy-options policy-statement nhs_test term a from protocol bgp
set policy-options policy-statement nhs_test term a from community red
set policy-options policy-statement nhs_test term a then next-hop 1.1.1.40
set policy-options policy-statement nhs_test term a then next policy
set policy-options policy-statement nhs_test term a then accept
set policy-options policy-statement nhs_test term b from protocol bgp
set policy-options policy-statement nhs_test term b from community blue
set policy-options policy-statement nhs_test term b then next-hop 2.2.2.40
set policy-options policy-statement nhs_test term b then next policy
set policy-options policy-statement nhs_test term b then accept
set policy-options policy-statement nhs_test term c then next-hop self
set policy-options community blue members target:50:50
set policy-options community red members target:40:40
set routing-options rib-groups mcast-rib import-rib inet.2
set routing-options autonomous-system 100
set routing-options resolution rib inet.2 resolution-ribs :red.inet.0
set routing-options resolution rib inet.2 resolution-ribs :blue.inet.0
set routing-options topologies family inet topology red
set routing-options topologies family inet topology blue

Device P1

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set interfaces ge-1/2/0 unit 5 description to-PE1
set interfaces ge-1/2/0 unit 5 family inet address 10.0.0.5/30
set interfaces ge-1/2/1 unit 13 description to-P3
set interfaces ge-1/2/1 unit 13 family inet address 10.0.0.13/30
set interfaces ge-1/2/2 unit 17 description to-P4
set interfaces ge-1/2/2 unit 17 family inet address 10.0.0.17/30
set interfaces ge-1/2/3 unit 33 description to-P2
set interfaces ge-1/2/3 unit 33 family inet address 10.0.0.33/30
set interfaces lo0 unit 99 family inet address 10.255.165.99/32 primary
set protocols bgp group ibgp type internal
set protocols bgp group ibgp local-address 10.255.165.99
set protocols bgp group ibgp family inet unicast
set protocols bgp group ibgp family inet multicast
set protocols bgp group ibgp neighbor 10.255.165.93
set protocols bgp group ibgp neighbor 10.255.165.111
set protocols bgp group ibgp neighbor 10.255.165.203
set protocols bgp group ibgp neighbor 10.255.165.95
set protocols bgp group ibgp neighbor 10.255.165.113
set protocols ospf topology red topology-id 126
set protocols ospf topology blue topology-id 52
set protocols ospf area 0.0.0.0 interface ge-1/2/3.33 metric 10
set protocols ospf area 0.0.0.0 interface ge-1/2/3.33 topology red
set protocols ospf area 0.0.0.0 interface ge-1/2/3.33 topology blue metric 1
set protocols ospf area 0.0.0.0 interface ge-1/2/2.17
set protocols ospf area 0.0.0.0 interface ge-1/2/1.13
set protocols ospf area 0.0.0.0 interface ge-1/2/0.5 metric 10
set protocols ospf area 0.0.0.0 interface ge-1/2/0.5 topology red
set protocols ospf area 0.0.0.0 interface ge-1/2/0.5 topology blue metric 1
set protocols ospf area 0.0.0.0 interface lo0.99 passive
set protocols pim rib-group inet mcast-rib
set protocols pim interface ge-1/2/3.33 mode sparse
set protocols pim interface ge-1/2/2.17 mode sparse
set protocols pim interface ge-1/2/1.13 mode sparse
set protocols pim interface ge-1/2/0.5 mode sparse
set routing-options rib-groups mcast-rib import-rib inet.2
set routing-options autonomous-system 100
set routing-options topologies family inet topology red
set routing-options topologies family inet topology blue

Device P2

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set interfaces ge-1/2/0 unit 22 description to-P3
set interfaces ge-1/2/0 unit 22 family inet address 10.0.0.22/30
set interfaces ge-1/2/1 unit 25 description to-P4
set interfaces ge-1/2/1 unit 25 family inet address 10.0.0.25/30
set interfaces ge-1/2/2 unit 34 description to-P1
set interfaces ge-1/2/2 unit 34 family inet address 10.0.0.34/30
set interfaces ge-1/2/3 unit 37 description to-PE2
set interfaces ge-1/2/3 unit 37 family inet address 10.0.0.37/30
set interfaces lo0 unit 113 family inet address 10.255.165.113/32 primary
set protocols bgp group ibgp type internal
set protocols bgp group ibgp local-address 10.255.165.113
set protocols bgp group ibgp family inet unicast
set protocols bgp group ibgp family inet multicast
set protocols bgp group ibgp neighbor 10.255.165.93
set protocols bgp group ibgp neighbor 10.255.165.111
set protocols bgp group ibgp neighbor 10.255.165.203
set protocols bgp group ibgp neighbor 10.255.165.95
set protocols bgp group ibgp neighbor 10.255.165.99
set protocols ospf topology red topology-id 126
set protocols ospf topology blue topology-id 52
set protocols ospf area 0.0.0.0 interface ge-1/2/2.34 metric 10
set protocols ospf area 0.0.0.0 interface ge-1/2/2.34 topology red
set protocols ospf area 0.0.0.0 interface ge-1/2/2.34 topology blue metric 1
set protocols ospf area 0.0.0.0 interface ge-1/2/0.22
set protocols ospf area 0.0.0.0 interface ge-1/2/1.25
set protocols ospf area 0.0.0.0 interface ge-1/2/3.37 metric 10
set protocols ospf area 0.0.0.0 interface ge-1/2/3.37 topology red
set protocols ospf area 0.0.0.0 interface ge-1/2/3.37 topology blue metric 1
set protocols ospf area 0.0.0.0 interface lo0.113 passive
set protocols pim rib-group inet mcast-rib
set protocols pim interface ge-1/2/2.34 mode sparse
set protocols pim interface ge-1/2/0.22 mode sparse
set protocols pim interface ge-1/2/1.25 mode sparse
set protocols pim interface ge-1/2/3.37 mode sparse
set routing-options rib-groups mcast-rib import-rib inet.2
set routing-options autonomous-system 100
set routing-options topologies family inet topology red
set routing-options topologies family inet topology blue

Device P3

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set interfaces ge-1/2/0 unit 10 description to-PE1
set interfaces ge-1/2/0 unit 10 family inet address 10.0.0.10/30
set interfaces ge-1/2/1 unit 14 description to-P1
set interfaces ge-1/2/1 unit 14 family inet address 10.0.0.14/30
set interfaces ge-1/2/2 unit 21 description to-P2
set interfaces ge-1/2/2 unit 21 family inet address 10.0.0.21/30
set interfaces ge-1/2/3 unit 29 description to-P4
set interfaces ge-1/2/3 unit 29 family inet address 10.0.0.29/30
set interfaces lo0 unit 111 family inet address 10.255.165.111/32 primary
set protocols bgp group ibgp type internal
set protocols bgp group ibgp local-address 10.255.165.111
set protocols bgp group ibgp family inet unicast
set protocols bgp group ibgp family inet multicast
set protocols bgp group ibgp neighbor 10.255.165.93
set protocols bgp group ibgp neighbor 10.255.165.113
set protocols bgp group ibgp neighbor 10.255.165.203
set protocols bgp group ibgp neighbor 10.255.165.95
set protocols bgp group ibgp neighbor 10.255.165.99
set protocols ospf topology red topology-id 126
set protocols ospf topology blue topology-id 52
set protocols ospf area 0.0.0.0 interface ge-1/2/3.29 metric 10
set protocols ospf area 0.0.0.0 interface ge-1/2/3.29 topology red metric 1
set protocols ospf area 0.0.0.0 interface ge-1/2/3.29 topology blue
set protocols ospf area 0.0.0.0 interface ge-1/2/2.21
set protocols ospf area 0.0.0.0 interface ge-1/2/1.14
set protocols ospf area 0.0.0.0 interface ge-1/2/0.10 metric 10
set protocols ospf area 0.0.0.0 interface ge-1/2/0.10 topology red metric 1
set protocols ospf area 0.0.0.0 interface ge-1/2/0.10 topology blue
set protocols ospf area 0.0.0.0 interface lo0.111 passive
set protocols pim rib-group inet mcast-rib
set protocols pim interface ge-1/2/3.29 mode sparse
set protocols pim interface ge-1/2/2.21 mode sparse
set protocols pim interface ge-1/2/1.14 mode sparse
set protocols pim interface ge-1/2/0.10 mode sparse
set routing-options rib-groups mcast-rib import-rib inet.2
set routing-options autonomous-system 100
set routing-options topologies family inet topology red
set routing-options topologies family inet topology blue

Device P4

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set interfaces ge-1/2/0 unit 18 description to-P1
set interfaces ge-1/2/0 unit 18 family inet address 10.0.0.18/30
set interfaces ge-1/2/1 unit 26 description to-P2
set interfaces ge-1/2/1 unit 26 family inet address 10.0.0.26/30
set interfaces ge-1/2/2 unit 30 description to-P3
set interfaces ge-1/2/2 unit 30 family inet address 10.0.0.30/30
set interfaces ge-1/2/3 unit 41 description to-PE2
set interfaces ge-1/2/3 unit 41 family inet address 10.0.0.41/30
set interfaces lo0 unit 95 family inet address 10.255.165.95/32 primary
set protocols bgp group ibgp type internal
set protocols bgp group ibgp local-address 10.255.165.95
set protocols bgp group ibgp family inet unicast
set protocols bgp group ibgp family inet multicast
set protocols bgp group ibgp neighbor 10.255.165.93
set protocols bgp group ibgp neighbor 10.255.165.113
set protocols bgp group ibgp neighbor 10.255.165.203
set protocols bgp group ibgp neighbor 10.255.165.111
set protocols bgp group ibgp neighbor 10.255.165.99
set protocols ospf topology red topology-id 126
set protocols ospf topology blue topology-id 52
set protocols ospf area 0.0.0.0 interface ge-1/2/2.30 metric 10
set protocols ospf area 0.0.0.0 interface ge-1/2/2.30 topology red metric 1
set protocols ospf area 0.0.0.0 interface ge-1/2/2.30 topology blue
set protocols ospf area 0.0.0.0 interface ge-1/2/0.18
set protocols ospf area 0.0.0.0 interface ge-1/2/1.26
set protocols ospf area 0.0.0.0 interface ge-1/2/3.41 metric 10
set protocols ospf area 0.0.0.0 interface ge-1/2/3.41 topology red metric 1
set protocols ospf area 0.0.0.0 interface ge-1/2/3.41 topology blue
set protocols ospf area 0.0.0.0 interface lo0.95 passive
set protocols pim rib-group inet mcast-rib
set protocols pim interface ge-1/2/2.30 mode sparse
set protocols pim interface ge-1/2/0.18 mode sparse
set protocols pim interface ge-1/2/1.26 mode sparse
set protocols pim interface ge-1/2/3.41 mode sparse
set routing-options rib-groups mcast-rib import-rib inet.2
set routing-options autonomous-system 100
set routing-options topologies family inet topology red
set routing-options topologies family inet topology blue

Configuring Device CE1

Step-by-Step Procedure
Results

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 Junos OS CLI User Guide.

To configure Device CE1:

Configure the interfaces.

For demonstration purposes, the example places an Ethernet interface into loopback mode and configures several addresses on this loopback interface. The addresses are then announced to the network as direct routes. These routes simulate a group of BGP routes with communities attached.

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[edit interfaces]
user@CE1# set fe-0/1/0 fastether-options loopback
user@CE1# set fe-0/1/0 unit 0 family inet address 11.19.130.1/24
user@CE1# set fe-0/1/0 unit 0 family inet address 11.19.131.1/24
user@CE1# set fe-0/1/0 unit 0 family inet address 11.19.132.1/24
user@CE1# set ge-1/2/0 unit 1 description to-PE1
user@CE1# set ge-1/2/0 unit 1 family inet address 10.0.0.1/30
user@CE1# set lo0 unit 97 family inet address 10.255.165.97/32 primary

Configure the external BGP (EBGP) connection to Device PE1.

The CE router nearest to the multicast servers announces the multicast source IP addresses to the PE routers using EBGP. The source addresses are announced with both family inet unicast and family inet multicast, thus causing the BGP route to be added to the default routing table, inet.0, and to the multicast routing table, inet.2. Both sets of routes are injected by the PE router into IBGP.
```
[edit protocols bgp group ebgp]
user@CE1# set type external
user@CE1# set local-address 10.0.0.1
user@CE1# set family inet unicast
user@CE1# set family inet multicast
user@CE1# set peer-as 100
user@CE1# set neighbor 10.0.0.2
```

Configure PIM on the interfaces.

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[edit protocols pim]
user@CE1# set interface fe-0/1/0.0 mode sparse
user@CE1# set interface ge-1/2/0.1 mode sparse

Configure the routing policy that announces the addresses that are configured on interface fe-0/1/0.

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[edit policy-options policy-statement inject_directs]
user@CE1# set term a from protocol direct
user@CE1# set term a from interface fe-0/1/0.0
user@CE1# set term a then next policy
user@CE1# set term a then accept
user@CE1# set term b then reject

Configure the routing policy that tags some routes with the red community attribute and other routes with the blue community attribute.

The CE router advertises routes through EBGP to the PE router. These routes are advertised as BGP family inet multicast routes with communities set for two different groups. Policies identify the two groups of BGP routes.

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[edit policy-options policy-statement set_community term a]
user@CE1# set from route-filter 11.19.130.0/24 exact
user@CE1# set from route-filter 11.19.131.0/24 exact
user@CE1# set then community add red
user@CE1# set then accept
[edit policy-options policy-statement set_community term b]
user@CE1# set from route-filter 11.19.132.0/24 exact
user@CE1# set from route-filter 11.19.133.0/24 exact
user@CE1# set then community add blue
user@CE1# set then accept
[edit policy-options policy-statement set_community term default]
user@CE1# set then accept
[edit policy-options]
user@CE1# set community blue members target:50:50
user@CE1# set community red members target:40:40

Apply the set_community export policy so that the direct routes are exported into BGP.

Apply the inject_directs export policy to announce the addresses that are configured on interface fe-0/1/0.
```
[edit protocols bgp group ebgp]
user@CE1# set export set_community
user@CE1# set export inject_directs
```

Use rib-groups to simulate a group of BGP routes with communities attached and announced as multicast routes.

This configuration creates a multicast routing table and causes PIM to use the multicast routing table inet.2.

content_copy zoom_out_map
[edit routing-options]
user@CE1# set interface-routes rib-group inet if-rib
user@CE1# set static route 10.0.0.0/16 next-hop 10.0.0.2
[edit routing-options rib-groups]
user@CE1# set inet.2 import-rib inet.0
user@CE1# set if-rib import-rib inet.0
user@CE1# set if-rib import-rib inet.2
user@CE1# set if-rib import-policy inject_directs

Configure the autonomous system (AS) number.
```
[edit routing-options]
user@CE1# set autonomous-system 101
```

Results

From configuration mode, confirm your configuration by entering the show interfaces, show protocols, show policy-options, and show routing-options commands. If the output does not display the intended configuration, repeat the instructions in this example to correct the configuration.

content_copy zoom_out_map
user@CE1# show interfaces
fe-0/1/0 {
    fastether-options {
        loopback;
    }
    unit 0 {
        family inet {
            address 11.19.130.1/24;
            address 11.19.131.1/24;
            address 11.19.132.1/24;
        }
    }
}
ge-1/2/0 {
    unit 1 {
        description to-PE1;
        family inet {
            address 10.0.0.1/30;
        }
    }
}
lo0 {
    unit 97 {
        family inet {
            address 10.255.165.97/32 {
                primary;
            }
        }
    }
}

content_copy zoom_out_map
user@CE1# show protocols
bgp {
    group ebgp {
        type external;
        local-address 10.0.0.1;
        family inet {
            unicast;
            multicast;
        }
        export [ set_community inject_directs ];
        peer-as 100;
        neighbor 10.0.0.2;
    }
}
pim {
    interface fe-0/1/0.0 {
        mode sparse;
    }
    interface ge-1/2/0.1 {
        mode sparse;
    }
}

content_copy zoom_out_map
user@CE1# show policy-options
policy-statement inject_directs {
    term a {
        from {
            protocol direct;
            interface fe-0/1/0.0;
        }
        then {
            next policy;
            accept;
        }
    }
    term b {
        then reject;
    }
}
policy-statement set_community {
    term a {
        from {
            route-filter 11.19.130.0/24 exact;
            route-filter 11.19.131.0/24 exact;
        }
        then {
            community add red;
            accept;
        }
    }
    term b {
        from {
            route-filter 11.19.132.0/24 exact;
            route-filter 11.19.133.0/24 exact;
        }
        then {
            community add blue;
            accept;
        }
    }
    term default {
        then accept;
    }
}
community blue members target:50:50;
community red members target:40:40;

content_copy zoom_out_map
user@CE1# show routing-options
interface-routes {
    rib-group inet if-rib;
}
static {
    route 10.0.0.0/16 next-hop 10.0.0.2;
}
rib-groups {
    inet.2 {
        import-rib inet.0;
    }
    if-rib {
        import-rib [ inet.0 inet.2 ];
        import-policy inject_directs;
    }
}
autonomous-system 101;

If you are done configuring the device, enter commit from configuration mode.

Configuring Device PE1

Step-by-Step Procedure
Results

Step-by-Step Procedure

To configure Device PE1:

Configure the interfaces.

content_copy zoom_out_map
[edit interfaces]
user@PE1# set ge-1/2/0 unit 2 description to-CE1
user@PE1# set ge-1/2/0 unit 2 family inet address 10.0.0.2/30
user@PE1# set ge-1/2/1 unit 6 description to-P1
user@PE1# set ge-1/2/1 unit 6 family inet address 10.0.0.6/30
user@PE1# set ge-1/2/2 unit 9 description to-P3
user@PE1# set ge-1/2/2 unit 9 family inet address 10.0.0.9/30
user@PE1# set lo0 unit 93 family inet address 10.255.165.93/32 primary

Configure secondary addresses, 1.1.1.30 and 2.2.2.30.

A specific protocol next-hop IP address is required for each topology on each router injecting IBGP routes. You can configure multiple secondary loopback IP addresses on a router to be used as protocol next-hop addresses. This configuration shows nonprimary IP addresses 1.1.1.30/32 and 2.2.2.30/32 configured on loopback interface lo0 for use in the red and blue topologies, respectively.

A group of BGP routes associated with a routing topology use the same unique protocol next hop. For instance, if you configure a PE router to handle two routing topologies, then you would also configure two unique nonprimary addresses under loopback interface lo0.
```
[edit interfaces]
user@PE1# set lo0 unit 93 family inet address 1.1.1.30/32
user@PE1# set lo0 unit 93 family inet address 2.2.2.30/32
```
Associate each nonprimary loopback IP address with a topology for inclusion in the associated topology routing table.

Configure the loopback IP address and topology under an OSPF interface statement. You must specifically disable all other topologies known to OSPF for two reasons. First, the loopback address specific to a topology must reside in only one topology routing table. Second, once the topology is added to OSPF, the topology defaults to being enabled on all subsequent interfaces under OSPF.

The Device PE1 configuration places the loopback address 1.1.1.30/32 into the OSPF database as a stub route under this router�s OSPF Router-LSA. It belongs to the red and default topologies, but not to the blue topology. The loopback address 1.1.1.30/32 is installed in the remote core routers� topology routing tables inet.0 and :red.inet.0, (but not in :blue.inet.0). Use a similar configuration for the blue loopback address 2.2.2.30/32.
```
[edit protocols ospf]
user@PE1# set topology red topology-id 126
user@PE1# set topology blue topology-id 52
[edit protocols ospf area 0.0.0.0]
user@PE1# set interface 1.1.1.30 topology red
user@PE1# set interface 1.1.1.30 topology blue disable
user@PE1# set interface 2.2.2.30 topology blue
user@PE1# set interface 2.2.2.30 topology red disable
```
Enable OSPF on the interfaces, and configure specific OSPF link metrics on topologies to identify paths and build trees to different servers.

Links can support all routing topologies to provide backup should a primary multicast path fail.

When a multicast tree gets built through PIM join messages directed toward the source, it follows the most preferred path. A multicast tree to a different multicast source (in a different routing topology) can create another tree along a different path.
```
[edit protocols ospf area 0.0.0.0]
user@PE1# set interface ge-1/2/1.6 metric 10
user@PE1# set interface ge-1/2/1.6 topology blue metric 1
user@PE1# set interface ge-1/2/1.6 topology red
user@PE1# set interface ge-1/2/2.9 metric 10
user@PE1# set interface ge-1/2/2.9 topology red metric 1
user@PE1# set interface ge-1/2/2.9 topology blue
user@PE1# set interface lo0.93 passive
```
Create the multicast routing table inet.2, and configure PIM to use the inet.2 routing table.

Set up a separate routing table for multicast lookups. It is populated with routes from inet.2. The inet.2 routing table is populated by routes of type multicast.
```
[edit routing-options]
user@PE1# set rib-groups mcast-rib import-rib inet.2
```
Configure PIM to use the routes in inet.2.
```
[edit protocols pim]
user@PE1# set rib-group inet mcast-rib
```

Enable PIM on the interfaces.

content_copy zoom_out_map
[edit protocols pim]
user@PE1# set interface ge-1/2/0.2 mode sparse
user@PE1# set interface ge-1/2/1.6 mode sparse
user@PE1# set interface ge-1/2/2.9 mode sparse

Configure the router to perform route resolution on protocol next hops using specified routing tables.

The protocol next hop is used to determine the forwarding next-hop interface out of which to forward PIM join messages. This configuration directs inet.2 route resolution to use topology routing tables :red.inet.0 and :blue.inet.0 for protocol next-hop IP address lookups.

You can specify up to two routing tables in the resolution configuration. A key element to this solution is that the protocol next-hop address resides in only one topology routing table. That is, the protocol next hop belongs to a remote PE secondary loopback address and is injected into only one topology routing table. The route resolution scheme first checks routing table :red.inet.0 for the protocol next-hop address. If the address is found, it uses this entry. If it is not found, the resolution scheme checks routing table :blue.inet.0. Hence, only one topology routing table is used for each protocol nexthop address.
```
[edit routing-options resolution rib inet.2]
user@PE1# set resolution-ribs :red.inet.0
user@PE1# set resolution-ribs :blue.inet.0
```
Configure the autonomous system (AS) number.
```
[edit routing-options]
user@PE1# set autonomous-system 100
```

Configure BGP.

content_copy zoom_out_map
[edit protocols bgp group ibgp]
user@PE1# set type internal
user@PE1# set local-address 10.255.165.93
user@PE1# set family inet unicast
user@PE1# set family inet multicast
user@PE1# set neighbor 10.255.165.111
user@PE1# set neighbor 10.255.165.203
user@PE1# set neighbor 10.255.165.113
user@PE1# set neighbor 10.255.165.95
user@PE1# set neighbor 10.255.165.99
[edit protocols bgp group ebgp]
user@PE1# set type external
user@PE1# set local-address 10.0.0.2
user@PE1# set family inet unicast
user@PE1# set family inet multicast
user@PE1# set peer-as 101
user@PE1# set neighbor 10.0.0.1

Set the protocol next hop when exporting EBGP routes into IBGP.

Configure the ingress Device PE1 router to set the BGP route�s protocol next-hop address when exporting the route into IBGP.

BGP uses an export policy to set the next hop when injecting the EBGP routes into IBGP.

This configuration is an export policy where there are three possibilities of next hops being set. Route 1.1.1.30 is associated with the red topology. Route 2.2.2.30 is associated with the blue topology. For the default next-hop self policy, the primary loopback address 10.255.165.93 on Device PE1 is used.

The nhs_test policy sets the protocol next-hop based on the community in the BGP update.

content_copy zoom_out_map
[edit policy-options]
user@PE1# set community blue members target:50:50
user@PE1# set community red members target:40:40
[edit policy-options policy-statement nhs_test term a]
user@PE1# set from protocol bgp
user@PE1# set from community red
user@PE1# set then next-hop 1.1.1.30
user@PE1# set then next policy
user@PE1# set then accept
[edit policy-options policy-statement nhs_test term b]
user@PE1# set from protocol bgp
user@PE1# set from community blue
user@PE1# set then next-hop 2.2.2.30
user@PE1# set then next policy
user@PE1# set then accept
user@PE1# set policy-options policy-statement nhs_test term c then next-hop self
[edit policy-options policy-statement nhs_inet0_self term a]
user@PE1# set from protocol bgp
user@PE1# set from rib inet.0
user@PE1# set then next-hop self

Apply the next-hop self policies to the IBGP sessions.

content_copy zoom_out_map
[edit protocols bgp group ibgp]
user@PE1# set export nhs_test
user@PE1# set export nhs_inet0_self

Configure the voice and video topologies, which enable you to use these topologies with OSPF and BGP.

The names voice and video are local to the router. The names are not propagated beyond this router. However, for management purposes, a consistent naming scheme across routers in a multitopology environment is convenient.
```
[edit routing-options topologies family inet]
user@PE1# set topology red
user@PE1# set topology blue
```

Results

From configuration mode, confirm your configuration by entering the show interfaces, show protocols, and show routing-options, and show policy-options commands. If the output does not display the intended configuration, repeat the instructions in this example to correct the configuration.

content_copy zoom_out_map
user@PE1# show interfaces
ge-1/2/0 {
    unit 2 {
        description to-CE1;
        family inet {
            address 10.0.0.2/30;
        }
    }
}
ge-1/2/1 {
    unit 6 {
        description to-P1;
        family inet {
            address 10.0.0.6/30;
        }
    }
}
ge-1/2/2 {
    unit 9 {
        description to-P3;
        family inet {
            address 10.0.0.9/30;
        }
    }
}
lo0 {
    unit 93 {
        family inet {
            address 10.255.165.93/32 {
                primary;
            }
            address 1.1.1.30/32;
            address 2.2.2.30/32;
        }
    }
}

content_copy zoom_out_map
user@PE1# show protocols
bgp {
    group ibgp {
        type internal;
        local-address 10.255.165.93;
        family inet {
            unicast;
            multicast;
        }
        export [ nhs_test nhs_inet0_self ];
        neighbor 10.255.165.111;
        neighbor 10.255.165.203;
        neighbor 10.255.165.113;
        neighbor 10.255.165.95;
        neighbor 10.255.165.99;
    }
    group ebgp {
        type external;
        local-address 10.0.0.2;
        family inet {
            unicast;
            multicast;
        }
        peer-as 101;
        neighbor 10.0.0.1;
    }
}
ospf {
    topology red topology-id 126;
    topology blue topology-id 52;
    area 0.0.0.0 {
        interface ge-1/2/1.6 {
            metric 10;
            topology blue metric 1;
            topology red;
        }
        interface ge-1/2/2.9 {
            metric 10;
            topology red metric 1;
            topology blue;
        }
        interface lo0.93 {
            passive;
        }
        interface 1.1.1.30 {
            topology red;
            topology blue disable;
        }
        interface 2.2.2.30 {
            topology blue;
            topology red disable;
        }
    }
}
pim {
    rib-group inet mcast-rib;
    interface ge-1/2/0.2 {
        mode sparse;
    }
    interface ge-1/2/1.6 {
        mode sparse;
    }
    interface ge-1/2/2.9 {
        mode sparse;
    }
}

content_copy zoom_out_map
user@PE1# show policy-options
policy-statement nhs_inet0_self {
    term a {
        from {
            protocol bgp;
            rib inet.0;
        }
        then {
            next-hop self;
        }
    }
}
policy-statement nhs_test {
    term a {
        from {
            protocol bgp;
            community red;
        }
        then {
            next-hop 1.1.1.30;
            next policy;
            accept;
        }
    }
    term b {
        from {
            protocol bgp;
            community blue;
        }
        then {
            next-hop 2.2.2.30;
            next policy;
            accept;
        }
    }
    term c {
        then {
            next-hop self;
        }
    }
}
community blue members target:50:50;
community red members target:40:40;

content_copy zoom_out_map
user@PE1# show routing-options
rib-groups {
    mcast-rib {
        import-rib inet.2;
    }
}
autonomous-system 100;
resolution {
    rib inet.2 {
        resolution-ribs [ :red.inet.0 :blue.inet.0 ];
    }
}
topologies {
    family inet {
        topology red;
        topology blue;
    }
}

If you are done configuring the device, enter commit from configuration mode.

Verification

Confirm that the configuration is working properly.

Checking the IBGP routes in inet.2
Verifying the Routes
Checking the Resolving BGP Next Hops
Examining the Protocol Next Hop
Verifying the OSPF Neighbor
Checking the Router LSA
Checking How Traffic Traverses the Network

Checking the IBGP routes in inet.2

Purpose
Action
Meaning

Purpose

Make sure that the routes injected into IBGP by Device PE1 have next hops that are based on the topology to which they belong.

Action

From operational mode, enter the show route table extensive command.

content_copy zoom_out_map
user@PE1> show route 11.19.130.0/24 table inet.2 extensive
inet.2: 3 destinations, 3 routes (3 active, 0 holddown, 0 hidden)
11.19.130.0/24 (1 entry, 1 announced)
TSI:
Page 0 idx 0 Type 1 val 93e9768
    Flags: Nexthop Change
    Nexthop: 1.1.1.30
    Localpref: 100
    AS path: [100] 101 I
    Communities: target:40:40
Path 11.19.130.0 from 10.0.0.1 Vector len 4.  Val: 0
        *BGP    Preference: 170/-101
                Next hop type: Router, Next hop index: 1180
                Address: 0x94003ec
                Next-hop reference count: 16
                Source: 10.0.0.1
                Next hop: 10.0.0.1 via lt-1/2/0.2, selected
                Session Id: 0x380004
                State: <Active Ext>
                Local AS:   100 Peer AS:   101
                Age: 22 
                Validation State: unverified 
                Task: BGP_101.10.0.0.1+58346
                Announcement bits (1): 0-BGP_RT_Background 
                AS path: 101 I
                Communities: target:40:40
                Accepted
                Localpref: 100
                Router ID: 10.255.165.97

Meaning

This output shows an IBGP route in the inet.2 routing table, as seen from Device PE1. The route was originally injected into IBGP by Device PE1, where the next hop was set based on the topology to which the route belonged. The BGP community value determined the topology association.

The route 11.19.130/24 belongs to the red topology because it has a community value of target:40:40. The protocol next hop is 1.1.1.30, and the forwarding next hop is ge-1/2/1.42.

Verifying the Routes

Purpose
Action
Meaning

Purpose

Make sure that the routes are in the expected routing tables and that the expected communities are attached to the routes.

Action

From operational mode, enter the show route detail command on Device PE1.

content_copy zoom_out_map
user@PE1> show route 11.19.130.0/24 detail
inet.0: 29 destinations, 30 routes (29 active, 0 holddown, 0 hidden)
11.19.130.0/24 (1 entry, 1 announced)
        *BGP    Preference: 170/-101
                Next hop type: Router, Next hop index: 812
                Address: 0xb9f064c
                Next-hop reference count: 22
                Source: 10.0.0.1
                Next hop: 10.0.0.1 via fe-1/2/0.2, selected
                Session Id: 0x600004
                State: <Active Ext>
                Local AS:   100 Peer AS:   101
                Age: 3d 21:44:07 
                Task: BGP_101.10.0.0.1+51873
                Announcement bits (3): 0-KRT 3-BGP_RT_Background 4-Resolve tree 3 
                AS path: 101 I
                Communities: target:40:40
                Accepted
                Localpref: 100
                Router ID: 10.255.165.97
                Secondary Tables: :voice.inet.0

:voice.inet.0: 16 destinations, 16 routes (16 active, 0 holddown, 0 hidden)

11.19.130.0/24 (1 entry, 1 announced)
        *BGP    Preference: 170/-101
                Next hop type: Router, Next hop index: 812
                Address: 0xb9f064c
                Next-hop reference count: 22
                Source: 10.0.0.1
                Next hop: 10.0.0.1 via fe-1/2/0.2, selected
                Session Id: 0x600004
                State: <Secondary Active IndepResolution Ext>
                Local AS:   100 Peer AS:   101
                Age: 3d 21:44:07 
                Task: BGP_101.10.0.0.1+51873
                Announcement bits (2): 0-KRT 1-Resolve tree 1 
                AS path: 101 I
                Communities: target:40:40
                Accepted
                Localpref: 100
                Router ID: 10.255.165.97
                Primary Routing Table inet.0

Meaning

This output shows BGP route 11.19.130.0/24 with community value target:40:40. Because the route matches the criteria for the voice topology, it is added to both the default and voice topology routing tables (inet.0 and :voice.inet.0). Device PE1 learns the route from Device CE1 through EBGP and then injects the route into IBGP.

Checking the Resolving BGP Next Hops

Purpose
Action
Meaning

Purpose

Check the protocol next hop and forwarding next hop.

Action

From operational mode, enter the show route detail command on Device PE2.

content_copy zoom_out_map
user@PE2> show route 11.19.130.0/24 detail
inet.0: 29 destinations, 30 routes (29 active, 0 holddown, 0 hidden)
11.19.130.0/24 (1 entry, 1 announced)
        *BGP    Preference: 170/-101
                Next hop type: Indirect
                Address: 0xb9f0e04
                Next-hop reference count: 12
                Source: 10.255.165.93
                Next hop type: Router, Next hop index: 262153
                Next hop: 10.0.0.37 via fe-1/2/0.38
                Session Id: 0x700004
                Next hop: 10.0.0.41 via fe-1/2/1.42, selected
                Session Id: 0x700005
                Protocol next hop: 10.255.165.93
                Indirect next hop: bb8c000 262154 INH Session ID: 0x700007
                State: <Active Int Ext>
                Local AS:   100 Peer AS:   100
                Age: 3d 4:27:40         Metric2: 30 
                Task: BGP_100.10.255.165.93+179
                Announcement bits (3): 0-KRT 3-BGP_RT_Background 4-Resolve tree 3 
                AS path: 101 I
                Communities: target:40:40
                Accepted
                Localpref: 100
                Router ID: 10.255.165.93
                Secondary Tables: :voice.inet.0

:voice.inet.0: 16 destinations, 16 routes (16 active, 0 holddown, 0 hidden)

11.19.130.0/24 (1 entry, 1 announced)
        *BGP    Preference: 170/-101
                Next hop type: Indirect
                Address: 0xb9f0f34
                Next-hop reference count: 6
                Source: 10.255.165.93
                Next hop type: Router, Next hop index: 1188
                Next hop: 10.0.0.37 via fe-1/2/0.38, selected
                Session Id: 0x700004
                Protocol next hop: 10.255.165.93
                Indirect next hop: bb8c1d8 262177 INH Session ID: 0x700007
                State: <Secondary Active IndepResolution Int Ext>
                Local AS:   100 Peer AS:   100
                Age: 3d 2:00:20         Metric2: 30 
                Task: BGP_100.10.255.165.93+179
                Announcement bits (2): 0-KRT 1-Resolve tree 1 
                AS path: 101 I
                Communities: target:40:40
                Accepted
                Localpref: 100          
                Router ID: 10.255.165.93
                Primary Routing Table inet.0

Meaning

A typical IBGP core has BGP routes with protocol next hops that resolve using the underlying IGP routes. IBGP routes in a topology routing table have protocol next-hop IP addresses. By default, the same topology routing table is used to look up and resolve the protocol next-hop IP address to a forwarding next hop. This output from Device PE2 shows the same BGP route as seen in the previous example: 11.19.130.0/24. The route is being shown from a different perspective, that is, from Device PE2 as an IBGP route. Similarly, this IBGP route is added to both inet.0 and :voice.inet.0 on Device PE2. However, while each route has the same protocol next hop, each route has a different forwarding next hop (ge-0/0/3.0 instead of ge-0/1/4.0). The reason for this difference is when the protocol next-hop IP address 10.255.165.93 is resolved, it uses the corresponding routing table (inet.0 or :voice.inet.0) to look up the protocol next hop.

Examining the Protocol Next Hop

Purpose
Action
Meaning

Purpose

Check the protocol next hop and forwarding next hop.

Action

From operational mode, enter the show route command on Device PE2.

content_copy zoom_out_map
user@PE2> show route 10.255.165.93
inet.0: 29 destinations, 30 routes (29 active, 0 holddown, 0 hidden)
+ = Active Route, - = Last Active, * = Both

10.255.165.93/32   *[OSPF/10] 3d 04:37:26, metric 30
                    > to 10.0.0.37 via fe-1/2/0.38
                      to 10.0.0.41 via fe-1/2/1.42

:voice.inet.0: 16 destinations, 16 routes (16 active, 0 holddown, 0 hidden)
+ = Active Route, - = Last Active, * = Both

10.255.165.93/32   *[OSPF/10] 3d 02:10:04, metric 30
                    > to 10.0.0.37 via fe-1/2/0.38

:video.inet.0: 16 destinations, 16 routes (16 active, 0 holddown, 0 hidden)
+ = Active Route, - = Last Active, * = Both

10.255.165.93/32   *[OSPF/10] 3d 02:03:16, metric 30
                    > to 10.0.0.41 via fe-1/2/1.42

Meaning

This output from Device PE2 shows the protocol next hop of 11.19.130.0/24, which is IP address 10.255.165.93, thus further demonstrating how IBGP route 11.19.130.0/24 resolves its protocol next hop. The forwarding next hops of 10.255.165.93 match the IBGP forwarding next hops of route 11.19.130/24 as shown in the previous example. Observe here that the IP address 10.255.165.93 is also in routing table :video.inet.0. This address is the loopback address of Device PE1, and as such, resides in all three routing tables. This example also shows how traffic entering Device PE2 destined to 11.19.130.0/24 exits different interfaces depending on its associated topology. The actual traffic is marked in such a way that a firewall filter can direct the traffic to use a particular topology routing table.

Verifying the OSPF Neighbor

Purpose
Action
Meaning

Purpose

Make sure that the expected topologies are enabled on the OSPF neighbor.

Action

From operational mode, enter the show (ospf | ospf3) neighbor extensive command on Device P2.

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user@P2> show ospf neighbor 10.0.0.21 extensive
Address          Interface              State     ID               Pri  Dead
10.0.0.21        fe-1/2/0.22            Full      10.255.165.111   128    39
  Area 0.0.0.0, opt 0x52, DR 10.0.0.22, BDR 10.0.0.21
  Up 3d 06:09:50, adjacent 3d 06:09:50
   Topology default (ID 0) -> Bidirectional
   Topology video (ID 52) -> Bidirectional

Meaning

This Device P2 output shows OSPF neighbor PE2 (10.0.0.21), where multitopology OSPF default and video are participants. The Bidirectional flag shows that the neighbor is configured using the same multitopology OSPF ID.

Checking the Router LSA

Purpose
Action
Meaning

Purpose

Check the links where video and voice topologies are enabled.

Action

From operational mode, enter the show ospf database extensive command on Device P2.

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user@P2> show ospf database lsa-id 10.255.165.203 extensive

    OSPF database, Area 0.0.0.0
 Type       ID               Adv Rtr           Seq      Age  Opt  Cksum  Len 
Router   10.255.165.203   10.255.165.203   0x80000063  1552  0x22 0xdff3  80
  bits 0x0, link count 3
  id 10.255.165.203, data 255.255.255.255, Type Stub (3)
    Topology count: 2, Default metric: 0
    Topology video (ID 52) -> Metric: 0
    Topology voice (ID 126) -> Metric: 0
  id 10.0.0.38, data 10.0.0.38, Type Transit (2)
    Topology count: 2, Default metric: 10
    Topology video (ID 52) -> Metric: 200
    Topology voice (ID 126) -> Metric: 10
  id 10.0.0.42, data 10.0.0.42, Type Transit (2)
    Topology count: 1, Default metric: 10
    Topology video (ID 52) -> Metric: 10
  Topology default (ID 0)
    Type: Transit, Node ID: 10.0.0.42
      Metric: 10, Bidirectional
    Type: Transit, Node ID: 10.0.0.38
      Metric: 10, Bidirectional
  Topology video (ID 52)
    Type: Transit, Node ID: 10.0.0.42
      Metric: 10, Bidirectional
    Type: Transit, Node ID: 10.0.0.38
      Metric: 200, Bidirectional
  Topology voice (ID 126)
    Type: Transit, Node ID: 10.0.0.38
      Metric: 10, Bidirectional
  Aging timer 00:34:08
  Installed 00:25:49 ago, expires in 00:34:08, sent 00:25:47 ago
  Last changed 3d 01:45:51 ago, Change count: 10

Meaning

This Device P2 output shows the Router-LSA originated by Device PE2. The LSA shows links where video and voice topologies are enabled (in addition to the default topology).

Checking How Traffic Traverses the Network

Purpose
Action

Purpose

Make sure that the expected paths are used.

Action

From operational mode, enter the traceroute command on Device CE1.

The first example output shows that a traceroute over the voice topology goes from Device CE1 to Device CE2 where DSCPs are set. The routes are resolved over :voice.inet.0. This traceroute path follows the voice path CE1-PE1-P1-P2-PE2-CE2.

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user@CE1> traceroute 11.19.140.1 source 11.19.130.1 tos 160
traceroute to 11.19.140.1 (11.19.140.1) from 11.19.130.1, 30 hops max, 40 byte packets
 1  10.0.0.2 (10.0.0.2)  2.015 ms  1.924 ms  1.770 ms
 2  10.0.0.5 (10.0.0.5)  1.890 ms  1.010 ms  0.974 ms
 3  10.0.0.34 (10.0.0.34)  0.986 ms  1.031 ms  0.973 ms
 4  10.0.0.38 (10.0.0.38)  1.213 ms  1.065 ms  1.154 ms
 5  11.19.140.1 (11.19.140.1)  1.696 ms  4.286 ms  1.332 ms

This output shows a traceroute from Device CE1 to Device CE2 for voice where no DSCPs are set. The routes are resolved over inet.0, and the resulting path is different from the previous case where the DSCPs are set. This traceroute path follows the default path CE1-PE1-P4-PE2-CE2.

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user@CE1> traceroute 11.19.140.1 source 11.19.130.1

traceroute to 11.19.140.1 (11.19.140.1) from 11.19.130.1, 30 hops max, 40 byte packets
 1  10.0.0.2 (10.0.0.2)  1.654 ms  1.710 ms  1.703 ms
 2  10.0.0.5 (10.0.0.5)  1.790 ms  1.045 ms  0.975 ms
 3  10.0.0.18 (10.0.0.18)  0.989 ms  1.041 ms  0.983 ms
 4  10.0.0.42 (10.0.0.42)  0.994 ms  1.036 ms  1.002 ms
 5  11.19.140.1 (11.19.140.1)  1.329 ms  2.248 ms  2.225 ms

This output shows a traceroute from Device CE1 to Device CE2 for video traffic where the firewall filter is based on the destination address. The routes are resolved over :video.inet.0. This traceroute follows the video path CE1-PE1-P3-P4-PE2-CE2.

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user@CE1> traceroute 11.19.142.1 source 11.19.132.1

traceroute to 11.19.142.1 (11.19.142.1) from 11.19.132.1, 30 hops max, 40 byte packets
 1  10.0.0.2 (10.0.0.2)  1.126 ms  1.300 ms  0.995 ms
 2  10.0.0.10 (10.0.0.10)  0.981 ms  1.018 ms  0.991 ms
 3  10.0.0.30 (10.0.0.30)  0.997 ms  1.886 ms  1.952 ms
 4  10.0.0.42 (10.0.0.42)  1.800 ms  1.038 ms  0.980 ms
 5  11.19.142.1 (11.19.142.1)  1.367 ms  1.352 ms  1.328 ms

This output shows a traceroute from Device CE1 to Device CE2 for video where DSCPs are set. The DSCP bits are directing Device PE1 to use the topology table :voice.inet.0. Because there is no entry in the voice routing table for the video routes, traffic is dropped.

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user@CE1> traceroute 11.19.142.1 source 11.19.132.1 tos 160

traceroute to 11.19.142.1 (11.19.142.1) from 11.19.132.1, 30 hops max, 40 byte packets
 1  10.0.0.2 (10.0.0.2)  1.135 ms !N  1.007 ms !N  0.954 ms !N

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Multitopology Routing User Guide

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Example: Configuring Multitopology Routing to Provide Redundancy for Multicast Traffic over Separate Network Paths

Requirements

Overview

Configuration

CLI Quick Configuration

Configuring Device CE1

Step-by-Step Procedure

Results

Configuring Device PE1

Step-by-Step Procedure

Results

Verification

Checking the IBGP routes in inet.2

Purpose

Action

Meaning

Verifying the Routes

Purpose

Action

Meaning

Checking the Resolving BGP Next Hops

Purpose

Action

Meaning

Examining the Protocol Next Hop

Purpose

Action

Meaning

Verifying the OSPF Neighbor

Purpose

Action

Meaning

Checking the Router LSA

Purpose

Action

Meaning

Checking How Traffic Traverses the Network

Purpose

Action

Related Documentation

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