Carrier Supporting Carrier with SROS

Carrier of Carriers or Carrier supporting Carrier is a hierarchical construct to allow a network provider to provide MPLS connectivity with relatively low complexity. While it is even simpler to build layer 2 circuits over a backhaul network, in some cases routed connectivity may be preferred as you have a common connection point to the far end regions without needing to concern yourself with the provisioning scale and bandwidth management of each path. While this is quite a large posting it is mainly to show the configuration and verification steps. The summary of actions to create a CsC configuration is at the end of the post if you run out of patience.

This Example will have a three router Carrier of Carriers Network Operator (SC-1, SC-2 and SC-3) providing connectivity between a customer (VPRN 200) with two regions – Region A (RA-1, RA-2 and RA-3) and Region B (RB-1, RB-2 and RB-3)

9 Router Carrier Supporting Carrier Topology

Prior to SROS version 14.0R4, a single RIB was used for both labeled and unlabeled prefixes. With 14.0R4, two RIBs were established (actually, two RIBs for IPv4 and another two for IPv6) – this demonstration will have half the routers using 12.0R6 and half running 14.0R8 to highlight the configuration differences. The routers that are running SROS 14.0R8 in this example are configured using the VSR-D model which has the Control Plane Module operating in a VM (VM-CP) independent of the Input/Output Module (VM-DP) each VM-CP and VM-DP is logically connected via Switch Fabric ports – this is transparent to the configuration and operation of the simulated routers.

The initial configurations for Region A without the CSC Uplink on RA-1 as as below. OSPF as the IGP, LDP signalled LSPs are used, RA-3 is the local VPN Route Reflector for AS65000, VPRN 123 is created on each router.

configure
system
    name "RA-1"
exit
card 1
    card-type iom3-xp-b
    mda 1
        mda-type m5-1gb-sfp-b
        no shutdown
    exit
    no shutdown
exit
port 1/1/1
    ethernet
    exit
    no shutdown
exit
    port 1/1/2
    ethernet
    exit
    no shutdown
exit
router
    interface "RA-2"
        address 1.1.2.1/29
        port 1/1/1
        no shutdown
    exit
    interface "RA-3"
        address 1.1.3.1/29
        port 1/1/2
        no shutdown
    exit
    interface "system"
        address 1.1.1.1/32
        no shutdown
     exit
     autonomous-system 65000
     ospf
         area 0.0.0.0
             interface "system"
                 no shutdown
             exit
             interface "RA-2"
                 no shutdown
             exit
             interface "RA-3"
                 no shutdown
             exit
         exit
     exit
    ldp
        interface-parameters
            interface "RA-2"
            exit
            interface "RA-3"
            exit
        exit
        no shutdown
    exit
    bgp
    split-horizon
    group "VPN-RR"
        family vpn-ipv4
        peer-as 65000
        neighbor 1.1.1.3
            description "RA-3"
        exit
     exit
     no shutdown
    exit
exit
service
    vprn 123 customer 1 create
        route-distinguisher 1.1.1.1:123
        auto-bind ldp
        vrf-target target:65000:123
        interface "Loop" create
            address 123.1.1.1/32
            loopback
        exit
        no shutdown
    exit
exit
exit all
configure
system
    name "RA-2"
exit
card 1
    card-type iom3-xp-b
    mda 1
        mda-type m5-1gb-sfp-b
        no shutdown
    exit
    no shutdown
exit
port 1/1/1
    ethernet
    exit
    no shutdown
exit
    port 1/1/2
    ethernet
    exit
    no shutdown
exit
router
    interface "RA-1"
        address 1.1.2.2/29
        port 1/1/1
        no shutdown
    exit
    interface "RA-3"
        address 1.2.3.2/29
        port 1/1/2
        no shutdown
    exit
    interface "system"
        address 1.1.1.2/32
        no shutdown
     exit
     autonomous-system 65000
     ospf
         area 0.0.0.0
             interface "system"
                 no shutdown
             exit
             interface "RA-1"
                 no shutdown
             exit
             interface "RA-3"
                 no shutdown
             exit
         exit
     exit
    ldp
        interface-parameters
            interface "RA-1"
            exit
            interface "RA-3"
            exit
        exit
        no shutdown
    exit
    bgp
    split-horizon
    group "VPN-RR"
        family vpn-ipv4
        peer-as 65000
        neighbor 1.1.1.3
            description "RA-3"
        exit
     exit
     no shutdown
    exit
exit
service
    vprn 123 customer 1 create
        route-distinguisher 1.1.1.2:123
        auto-bind ldp
        vrf-target target:65000:123
        interface "Loop" create
            address 123.1.1.2/32
            loopback
        exit
        no shutdown
    exit
exit
exit all
configure
system
    name "RA-3"
exit
card 1
    card-type iom3-xp-b
    mda 1
        mda-type m5-1gb-sfp-b
        no shutdown
    exit
    no shutdown
exit
port 1/1/1
    ethernet
    exit
    no shutdown
exit
    port 1/1/2
    ethernet
    exit
    no shutdown
exit
router
    interface "RA-1"
        address 1.1.3.3/29
        port 1/1/1
        no shutdown
    exit
    interface "RA-2"
        address 1.2.3.3/29
        port 1/1/2
        no shutdown
    exit
    interface "system"
        address 1.1.1.3/32
        no shutdown
     exit
     autonomous-system 65000
     ospf
         area 0.0.0.0
             interface "system"
                 no shutdown
             exit
             interface "RA-1"
                 no shutdown
             exit
             interface "RA-2"
                 no shutdown
             exit
         exit
     exit
    ldp
        interface-parameters
            interface "RA-1"
            exit
            interface "RA-2"
            exit
        exit
        no shutdown
    exit
    bgp
    split-horizon
    group "VPN-RRC"
        family vpn-ipv4
        cluster 1.1.1.3
        peer-as 65000
        neighbor 1.1.1.1
            description "RA-1"
        exit
        neighbor 1.1.1.2
            description "RA-2"
        exit
     exit
     no shutdown
    exit
exit
service
    vprn 123 customer 1 create
        route-distinguisher 1.1.1.3:123
        auto-bind ldp
        vrf-target target:65000:123
        interface "Loop" create
            address 123.1.1.3/32
            loopback
        exit
        no shutdown
    exit
exit
exit all

Similarly for Region B, the initial configurations without the CSC Uplink on RB-1 as as below. OSPF as the IGP, LDP signalled LSPs, RB-3 is the local VPN Route Reflector for AS65000, VPRN 123 is created on each router. Besides the card/mda differences on the emulated hardware, the primary difference here compared to Region A which is using an older SROS version is the LSP binding (auto-bind) syntax changes to give more control as to the LSP types that may be desired.

configure
    system
        name "RB-1"
    exit
    sfm 1
        sfm-type m-sfm5-12
        no shutdown
    exit
    card 1
        card-type iom3-xp-b
        mda 1
            mda-type m10-1gb-xp-sfp
            no shutdown
        exit
        no shutdown
    exit
    port 1/1/1
        ethernet
        exit
        no shutdown
    exit
    port 1/1/2
        ethernet
        exit
        no shutdown
    exit
    router
        interface "RB-2"
            address 2.1.2.1/29
            port 1/1/1
            no shutdown
        exit
        interface "RB-3"
        address 2.1.3.1/29
            port 1/1/2
            no shutdown
        exit
        interface "system"
            address 2.2.2.1/32
            no shutdown
        exit
        autonomous-system 65000
        ospf 0
            area 0.0.0.0
                interface "system"
                    no shutdown
                exit
                interface "RB-2"
                    no shutdown
                exit
                interface "RB-3"
                    no shutdown
                exit
            exit
            no shutdown
        exit
        ldp
            interface-parameters
                interface "RB-2" dual-stack
                    ipv4
                        fec-type-capability
                        prefix-ipv6 disable
                            p2mp-ipv6 disable
                        exit
                        no shutdown
                    exit
                    no shutdown
                exit
                interface "RB-3" dual-stack
                    ipv4
                        fec-type-capability
                        prefix-ipv6 disable
                            p2mp-ipv6 disable
                        exit
                        no shutdown
                    exit
                    no shutdown
                exit
            exit
            no shutdown
        exit
        bgp
            split-horizon
            group "VPN-RR"
                family vpn-ipv4
                peer-as 65000
                neighbor 2.2.2.3
                    description "RB-3"
                exit
            exit
            no shutdown
        exit
    exit
    service
        vprn 123 customer 1 create
            route-distinguisher 2.2.2.1:123
            auto-bind-tunnel
                resolution-filter
                    ldp
                exit
                resolution filter
            exit
            vrf-target target:65000:123
            interface "Loop" create
                address 123.2.2.1/32
                loopback
            exit
        no shutdown
    exit
exit
exit all
configure
    system
        name "RB-2"
    exit
    sfm 1
        sfm-type m-sfm5-12
        no shutdown
    exit
    card 1
        card-type iom3-xp-b
        mda 1
            mda-type m10-1gb-xp-sfp
            no shutdown
        exit
        no shutdown
    exit
    port 1/1/1
        ethernet
        exit
        no shutdown
    exit
    port 1/1/2
        ethernet
        exit
        no shutdown
    exit
    router
        interface "RB-1"
            address 2.1.2.2/29
            port 1/1/1
            no shutdown
        exit
        interface "RB-3"
        address 2.2.3.2/29
            port 1/1/2
            no shutdown
        exit
        interface "system"
            address 2.2.2.2/32
            no shutdown
        exit
        autonomous-system 65000
        ospf 0
            area 0.0.0.0
                interface "system"
                    no shutdown
                exit
                interface "RB-1"
                    no shutdown
                exit
                interface "RB-3"
                    no shutdown
                exit
            exit
            no shutdown
        exit
        ldp
            interface-parameters
                interface "RB-1" dual-stack
                    ipv4
                        fec-type-capability
                        prefix-ipv6 disable
                            p2mp-ipv6 disable
                        exit
                        no shutdown
                    exit
                    no shutdown
                exit
                interface "RB-3" dual-stack
                    ipv4
                        fec-type-capability
                        prefix-ipv6 disable
                            p2mp-ipv6 disable
                        exit
                        no shutdown
                    exit
                    no shutdown
                exit
            exit
            no shutdown
        exit
        bgp
            split-horizon
            group "VPN-RR"
                family vpn-ipv4
                peer-as 65000
                neighbor 2.2.2.3
                    description "RB-3"
                exit
            exit
            no shutdown
        exit
    exit
    service
        vprn 123 customer 1 create
            route-distinguisher 2.2.2.2:123
            auto-bind-tunnel
                resolution-filter
                    ldp
                exit
                resolution filter
            exit
            vrf-target target:65000:123
            interface "Loop" create
                address 123.2.2.2/32
                loopback
            exit
        no shutdown
    exit
exit
exit all
configure
    system
        name "RB-3"
    exit
    sfm 1
        sfm-type m-sfm5-12
        no shutdown
    exit
    card 1
        card-type iom3-xp-b
        mda 1
            mda-type m10-1gb-xp-sfp
            no shutdown
        exit
        no shutdown
    exit
    port 1/1/1
        ethernet
        exit
        no shutdown
    exit
    port 1/1/2
        ethernet
        exit
        no shutdown
    exit
    router
        interface "RB-1"
            address 2.1.3.3/29
            port 1/1/1
            no shutdown
        exit
        interface "RB-2"
        address 2.2.3.3/29
            port 1/1/2
            no shutdown
        exit
        interface "system"
            address 2.2.2.3/32
            no shutdown
        exit
        autonomous-system 65000
        ospf 0
            area 0.0.0.0
                interface "system"
                    no shutdown
                exit
                interface "RB-1"
                    no shutdown
                exit
                interface "RB-2"
                    no shutdown
                exit
            exit
            no shutdown
        exit
        ldp
            interface-parameters
                interface "RB-1" dual-stack
                    ipv4
                        fec-type-capability
                        prefix-ipv6 disable
                            p2mp-ipv6 disable
                        exit
                        no shutdown
                    exit
                    no shutdown
                exit
                interface "RB-2" dual-stack
                    ipv4
                        fec-type-capability
                        prefix-ipv6 disable
                            p2mp-ipv6 disable
                        exit
                        no shutdown
                    exit
                    no shutdown
                exit
            exit
            no shutdown
        exit
        bgp
            split-horizon
            group "VPN-RRC"
                family vpn-ipv4
                peer-as 65000
                cluster-id 2.2.2.3				
                neighbor 2.2.2.1
                    description "RB-1"
                exit
                neighbor 2.2.2.2
                    description "RB-2"
                exit
            exit
            no shutdown
        exit
    exit
    service
        vprn 123 customer 1 create
            route-distinguisher 2.2.2.3:123
            auto-bind-tunnel
                resolution-filter
                    ldp
                exit
                resolution filter
            exit
            vrf-target target:65000:123
            interface "Loop" create
                address 123.2.2.3/32
                loopback
            exit
        no shutdown
    exit
exit
exit all

The CSC Operators Network uses IS-IS as the IGP, RSVP-TE signalled LSPs, SC-R3 is the local VPN Route Reflector for AS64512.

configure
    system
        name "SC-R1"
    exit
    card 1
        card-type iom3-xp-b
        mda 1
            mda-type m5-1gb-sfp-b
            no shutdown
        exit
        no shutdown
    exit
    port 1/1/1
        ethernet
        exit
        no shutdown
    exit
    port 1/1/2
        ethernet
        exit
        no shutdown
    exit
    router
        interface "SC-R2"
            address 10.1.2.1/29
            port 1/1/1
            no shutdown
        exit
        interface "SC-R3"
            address 10.1.3.1/29
            port 1/1/2
            no shutdown
        exit
        interface "system"
            address 10.10.10.1/32
            no shutdown
        exit
        autonomous-system 64512
        isis
            level-capability level-2
            area-id 49.0001
            traffic-engineering
            interface "system"
                no shutdown
            exit
            interface "SC-R2"
                no shutdown
            exit
            interface "SC-R3"
                no shutdown
            exit
            no shutdown
        exit
        mpls
            interface "system"
                no shutdown
            exit
            interface "SC-R2"
                no shutdown
            exit
            interface "SC-R3"
                no shutdown
            exit
            path "LOOSE_HOPS"
            no shutdown
            exit
            lsp "SC-R2"
                to 10.10.10.2
                cspf
                adspec
                fast-reroute facility
                exit
                primary "LOOSE_HOPS"
                exit
                no shutdown
            exit
            lsp "SC-R3"
                to 10.10.10.3
                cspf
                adspec
                fast-reroute facility
                exit
                primary "LOOSE_HOPS"
                exit
                no shutdown
            exit
            no shutdown
        exit
        rsvp
            interface "system"
                no shutdown
            exit
            interface "SC-R2"
                no shutdown
            exit
            interface "SC-R3"
                no shutdown
            exit
            no shutdown
        exit
        bgp
            group "IBGP"
                family vpn-ipv4
                peer-as 64512
                neighbor 10.10.10.3
                    description "SC-R3"
                exit
            exit
            no shutdown
        exit
    exit
exit all
configure
    system
        name "SC-R2"
    exit
    sfm 1
        sfm-type m-sfm5-12
        no shutdown
    exit
    card 1
        card-type iom3-xp-b
        mda 1
            mda-type m10-1gb-xp-sfp
            no shutdown
        exit
        no shutdown
    exit
    port 1/1/1
        ethernet
        exit
        no shutdown
    exit
    port 1/1/2
        ethernet
        exit
        no shutdown
    exit
    router
        interface "SC-R1"
            address 10.1.2.2/29
            port 1/1/1
            no shutdown
        exit
        interface "SC-R3"
            address 10.2.3.2/29
            port 1/1/2
            no shutdown
        exit
        interface "system"
            address 10.10.10.2/32
            no shutdown
        exit
        autonomous-system 64512
        isis 0
            level-capability level-2
            area-id 49.0001
            traffic-engineering
            interface "system"
                no shutdown
            exit
            interface "SC-R1"
                no shutdown
            exit
            interface "SC-R3"
                no shutdown
            exit
            no shutdown
        exit
        mpls
            interface "system"
                no shutdown
            exit
            interface "SC-R1"
                no shutdown
            exit
            interface "SC-R3"
                no shutdown
            exit
            path "LOOSE_HOPS"
                no shutdown
            exit
            lsp "SC-R3"
                to 10.10.10.3
                cspf
                adspec
                fast-reroute facility
                exit
                primary "LOOSE_HOPS"
                exit
                no shutdown
            exit
            lsp "SC-R1"
                to 10.10.10.1
                cspf
                adspec
                fast-reroute facility
                exit
                primary "LOOSE_HOPS"
                exit
                no shutdown
            exit
            no shutdown
        exit
        rsvp
            interface "system"
                no shutdown
            exit
            interface "SC-R1"
                no shutdown
            exit
            interface "SC-R3"
                no shutdown
            exit
            no shutdown
        exit
        bgp
            group "IBGP"
                family vpn-ipv4
                peer-as 64512
                neighbor 10.10.10.3
                    description "SC-R3"
                exit
            exit
            no shutdown
        exit
    exit
exit all
configure
    system
        name "SC-R3"
    exit
    card 1
        card-type iom3-xp-b
        mda 1
            mda-type m5-1gb-sfp-b
            no shutdown
        exit
        no shutdown
    exit
    port 1/1/1
        ethernet
        exit
        no shutdown
    exit
    port 1/1/2
        ethernet
        exit
        no shutdown
    exit
    router
        interface "SC-R1"
            address 10.1.3.3/29
            port 1/1/1
            no shutdown
        exit
        interface "SC-R2"
            address 10.2.3.3/29
            port 1/1/2
            no shutdown
        exit
        interface "system"
            address 10.10.10.3/32
            no shutdown
        exit
        autonomous-system 64512
        isis
            level-capability level-2
            area-id 49.0001
            traffic-engineering
            interface "system"
                no shutdown
            exit
            interface "SC-R1"
                no shutdown
            exit
            interface "SC-R2"
                no shutdown
            exit
            no shutdown
        exit
        mpls
            interface "system"
                no shutdown
            exit
            interface "SC-R1"
                no shutdown
            exit
            interface "SC-R2"
                no shutdown
            exit
            path "LOOSE_HOPS"
                no shutdown
            exit
            lsp "SC-R1"
                to 10.10.10.1
                cspf
                adspec
                fast-reroute facility
                exit
                primary "LOOSE_HOPS"
                exit
                no shutdown
            exit
            lsp "SC-R2"
                to 10.10.10.2
                cspf
                adspec
                fast-reroute facility
                exit
                primary "LOOSE_HOPS"
                exit
                no shutdown
            exit
            no shutdown
        exit
        rsvp
            interface "system"
                no shutdown
            exit
            interface "SC-R1"
                no shutdown
            exit
            interface "SC-R2"
                no shutdown
            exit
            no shutdown
        exit
        bgp
            group "IBGP"
                family vpn-ipv4
                cluster 10.10.10.3
                peer-as 64512
                neighbor 10.10.10.1
                    description "SC-R1"
                exit
                neighbor 10.10.10.2
                    description "SC-R2"
                exit
            exit
            no shutdown
        exit
    exit
exit all

At this stage, we have three Islands – Region A, Region B and the Carrier of Carriers Network (without the CSC configuration)

RA-1 is the Region A CSC-CE Router (which is also operating as a regular PE Router) which peers with the CSC Network SC-R1 to exchange labeled routes using BGP. Note: Both of these routers are running SROS 12.0R6 and are configured in the “old way”

Create VPRN 200 on SC-R1 and BGP Peering for RA-1:

configure
    router
        policy-options
            begin
            policy-statement "PS_MPBGP_VPN_TO_BGP"
                entry 10
                    from
                        protocol bgp-vpn
                    exit
                    action accept
                    exit
                exit
                default-action reject
            exit
            commit
        exit
    exit
    port 1/1/3
        ethernet
            mode network
        exit
        no shutdown
    exit
    service
        vprn 200 customer 1 create
            carrier-carrier-vpn
            autonomous-system 64512
            route-distinguisher 10.10.10.1:200
            auto-bind rsvp-te
            vrf-target target:64512:200
            network-interface "RA-1" create
                address 10.1.1.11/24
                port 1/1/3
                no shutdown
            exit
            bgp
                split-horizon
                group "RegionA"
                    family ipv4
                    as-override
                    export "PS_MPBGP_VPN_TO_BGP"
                    peer-as 65000
                    neighbor 10.1.1.1
                        advertise-label ipv4
                    exit
                exit
                no shutdown
            exit
            no shutdown
        exit
    exit
exit all

Of note is the definition of the VPRN type: carrier-carrier-vpn, once enabled regular IP interfaces cannot be created, only “network-interfaces” which must be on Ethernet ports that are of mode network. As both Region A and Region B both use AS 65000, as-override has been used to stop AS-Path loops occurring when advertising prefixes from other regions with the same BGP AS. We are using the IPv4 Address family but are specifically advertising associated MPLS Labels (This particular configuration component is different after SROS Release 14.0R4) Routing policy is defined and used to export VPN routes to RA-1.

Create the BGP Peering for RA-1 with SC-R1:

configure
    port 1/1/3
        ethernet
            mode network
        exit
        no shutdown
    exit
    router
        interface "SC-R1"
            address 10.1.1.1/24
            port 1/1/3
            no shutdown
        exit
        policy-options
            begin
            prefix-list "RegionA"
                prefix 1.1.1.0/24 prefix-length-range 32-32
            exit	
            policy-statement "PS_BGP_EXP_CSC"
                entry 10
                    from
                        prefix-list RegionA
                    exit
                    action accept
                    exit
                exit
                default-action reject
            exit
            commit
        exit
        bgp
            group "CSC"
                export "PS_BGP_EXP_CSC"
                    neighbor 10.1.1.11
                        description "SC-R1"
                        peer-as 64512
                        advertise-label ipv4 include-ldp-prefix
                    exit
                exit
                no shutdown
            exit
        exit
    exit
exit all

Routing policy is used to advertise any system addresses from Region A (1.1.1.x/32) with MPLS labels to the CSC

RB-1 is the Region B CSC-CE Router (which is also operating as a regular PE Router) which peers with the CSC Network SC-R2 to exchange labeled routes using BGP. Note: Both of these routers are running SROS 14.0R8 and are configured in the “new way”

Create VPRN 200 on SC-R2 and BGP Peering for RB-1:

configure
    router
        policy-options
            begin
            policy-statement "PS_MPBGP_VPN_TO_BGP"
                entry 10
                    from
                        protocol bgp-vpn
                    exit
                    action accept
                    exit
                exit
                default-action reject
            exit
           commit
        exit
    exit
    port 1/1/3
        ethernet
            mode network
        exit
        no shutdown
    exit
    service
        vprn 200 customer 1 create
            carrier-carrier-vpn
            autonomous-system 64512
            route-distinguisher 10.10.10.2:200
            auto-bind-tunnel
                resolution-filter
                    rsvp
                exit
                resolution filter
            exit
            vrf-target target:64512:200
            network-interface "RB-1" create
                address 10.2.2.11/24
                port 1/1/3
                no shutdown
            exit
            bgp
                split-horizon
                group "RB"
                    family label-ipv4
                    as-override
                    export "PS_MPBGP_VPN_TO_BGP"
                    peer-as 65000
                    neighbor 10.2.2.1
                    exit
                exit
                no shutdown
            exit
            no shutdown
        exit
    exit
exit all

The main difference compared with the configuration on SC-1 besides the auto-bind-tunnel changes, are that we are specifically peering using the label-ipv4 address family instead of the ipv4 address family and advertising labels.

Create the BGP Peering for RB-1 with SC-R2:

configure
    port 1/1/3
        ethernet
            mode network
        exit
        no shutdown
    exit
    router
        interface "SC-R2"
            address 10.2.2.1/24
            port 1/1/3
            no shutdown
        exit
        policy-options
            begin
            prefix-list "RegionB"
                prefix 2.2.2.0/24 prefix-length-range 32-32
            exit
            policy-statement "PS_BGP_EXP_CSC"
                entry 10
                    from
                        prefix-list "RegionB"
                    exit
                    action accept
                    exit
                exit
                default-action reject
            exit
            commit
        exit
        bgp
            group "CSC"
                export "PS_BGP_EXP_CSC"
                neighbor 10.2.2.11
                    description "SC-R2"
                    family label-ipv4
                    peer-as 64512
                    advertise-ldp-prefix
                exit
            exit
        exit
exit all

Routing policy is used to advertise any system addresses from Region B (2.2.2.x/32) with MPLS labels to the CSC

Once all peers are configured, examine the CSC VPRN 200 Routing Tables:

A:SC-R1#  show router 200 route-table

===============================================================================
Route Table (Service: 200)
===============================================================================
Dest Prefix[Flags]                            Type    Proto     Age        Pref
    Next Hop[Interface Name]                                    Metric
-------------------------------------------------------------------------------
1.1.1.1/32                                    Remote  BGP       00h07m55s  170
    10.1.1.1                                                     0
1.1.1.2/32                                    Remote  BGP       00h07m55s  170
    10.1.1.1                                                     0
1.1.1.3/32                                    Remote  BGP       00h07m55s  170
    10.1.1.1                                                     0
2.2.2.1/32                                    Remote  BGP VPN   00h07m28s  170
    10.10.10.2 (tunneled:RSVP:1)                                 0
2.2.2.2/32                                    Remote  BGP VPN   00h07m28s  170
    10.10.10.2 (tunneled:RSVP:1)                                 0
2.2.2.3/32                                    Remote  BGP VPN   00h07m28s  170
    10.10.10.2 (tunneled:RSVP:1)                                 0
10.1.1.0/24                                   Local   Local     00h08m29s  0
    RA-1                                                         0
10.2.2.0/24                                   Remote  BGP VPN   00h07m28s  170
    10.10.10.2 (tunneled:RSVP:1)                                 0
-------------------------------------------------------------------------------
No. of Routes: 8
Flags: n = Number of times nexthop is repeated
B = BGP backup route available
L = LFA nexthop available
S = Sticky ECMP requested
===============================================================================
A:SC-R2# show router 200 route-table

===============================================================================
Route Table (Service: 200)
===============================================================================
Dest Prefix[Flags]                            Type    Proto     Age        Pref
    Next Hop[Interface Name]                                    Metric
-------------------------------------------------------------------------------
1.1.1.1/32                                    Remote  BGP VPN   00h07m20s  170
    10.10.10.1 (tunneled:RSVP:2)                                 0
1.1.1.2/32                                    Remote  BGP VPN   00h07m20s  170
    10.10.10.1 (tunneled:RSVP:2)                                 0
1.1.1.3/32                                    Remote  BGP VPN   00h07m20s  170
    10.10.10.1 (tunneled:RSVP:2)                                 0
2.2.2.1/32                                    Remote  BGP_LABEL 02h02m23s  170
    10.2.2.1                                                     0
2.2.2.2/32                                    Remote  BGP_LABEL 02h02m23s  170
    10.2.2.1                                                     0
2.2.2.3/32                                    Remote  BGP_LABEL 02h02m23s  170
    10.2.2.1                                                     0
10.1.1.0/24                                   Remote  BGP VPN   00h07m20s  170
    10.10.10.1 (tunneled:RSVP:2)                                 0
10.2.2.0/24                                   Local   Local     02h11m42s  0
    RB-1                                                         0
-------------------------------------------------------------------------------
No. of Routes: 8
Flags: n = Number of times nexthop is repeated
B = BGP backup route available
L = LFA nexthop available
S = Sticky ECMP requested
===============================================================================

With Region A and Region B connectivity via the CSC we should be able to see the initial list of tunnels on the CSC-CE routers (RA-1 and RA-2):

A:RA-1# show router tunnel-table

===============================================================================
Tunnel Table (Router: Base)
===============================================================================
Destination           Owner Encap TunnelId  Pref     Nexthop        Metric
-------------------------------------------------------------------------------
1.1.1.2/32            ldp   MPLS   -        9        1.1.2.2        100
1.1.1.3/32            ldp   MPLS   -        9        1.1.3.3        100
2.2.2.1/32            bgp   MPLS   -        10       10.1.1.11      1000
2.2.2.2/32            bgp   MPLS   -        10       10.1.1.11      1000
2.2.2.3/32            bgp   MPLS   -        10       10.1.1.11      1000
-------------------------------------------------------------------------------
Flags: B = BGP backup route available
E = inactive best-external BGP route
===============================================================================
A:RB-1# show router tunnel-table

===============================================================================
IPv4 Tunnel Table (Router: Base)
===============================================================================
Destination       Owner     Encap TunnelId  Pref     Nexthop        Metric
-------------------------------------------------------------------------------
1.1.1.1/32        bgp       MPLS  262301    12       10.2.2.11      1000
1.1.1.2/32        bgp       MPLS  262303    12       10.2.2.11      1000
1.1.1.3/32        bgp       MPLS  262304    12       10.2.2.11      1000
2.2.2.2/32        ldp       MPLS  65540     9        2.1.2.2        100
2.2.2.3/32        ldp       MPLS  65541     9        2.1.3.3        100
-------------------------------------------------------------------------------
Flags: B = BGP backup route available
E = inactive best-external BGP route
===============================================================================
A:RA-2# show router tunnel-table

===============================================================================
Tunnel Table (Router: Base)
===============================================================================
Destination           Owner Encap TunnelId  Pref     Nexthop        Metric
-------------------------------------------------------------------------------
1.1.1.1/32            ldp   MPLS   -        9        1.1.2.1        100
1.1.1.3/32            ldp   MPLS   -        9        1.2.3.3        100
-------------------------------------------------------------------------------
Flags: B = BGP backup route available
E = inactive best-external BGP route
===============================================================================
A:RA-3# show router tunnel-table

===============================================================================
Tunnel Table (Router: Base)
===============================================================================
Destination           Owner Encap TunnelId  Pref     Nexthop        Metric
-------------------------------------------------------------------------------
1.1.1.1/32            ldp   MPLS   -        9        1.1.3.1        100
1.1.1.2/32            ldp   MPLS   -        9        1.2.3.2        100
-------------------------------------------------------------------------------
Flags: B = BGP backup route available
E = inactive best-external BGP route
===============================================================================
A:RB-2# show router tunnel-table

===============================================================================
IPv4 Tunnel Table (Router: Base)
===============================================================================
Destination       Owner     Encap TunnelId  Pref     Nexthop        Metric
-------------------------------------------------------------------------------
2.2.2.1/32        ldp       MPLS  65596     9        2.1.2.1        100
2.2.2.3/32        ldp       MPLS  65544     9        2.2.3.3        100
-------------------------------------------------------------------------------
Flags: B = BGP backup route available
E = inactive best-external BGP route
===============================================================================
A:RB-3# show router tunnel-table


===============================================================================
IPv4 Tunnel Table (Router: Base)
===============================================================================
Destination       Owner     Encap TunnelId  Pref     Nexthop        Metric
-------------------------------------------------------------------------------
2.2.2.1/32        ldp       MPLS  65597     9        2.1.3.1        100
2.2.2.2/32        ldp       MPLS  65537     9        2.2.3.2        100
-------------------------------------------------------------------------------
Flags: B = BGP backup route available
E = inactive best-external BGP route
===============================================================================

RA-2, RA-3, RB-2 and RB-3 need the CSC-CEs to to redistribute the prefixes we learnt from the CSC into OSPF and LDP.

configure
    router
        policy-options
            begin
            prefix-list "RegionB"
                prefix 2.2.2.0/24 prefix-length-range 32-32
            exit
            policy-statement "PS_OSPF_LDP_EXP_RB"
                entry 10
                    from
                        prefix-list "RegionB"
                    exit
                    action accept
                    exit
                exit
                default-action reject
            exit
            commit
        exit
        ospf
            asbr
            export "PS_OSPF_LDP_EXP_RB"
        exit
        ldp
            export-tunnel-table "PS_OSPF_LDP_EXP_RB"
        exit
    exit
exit all
configure
    router
        policy-options
            begin
            prefix-list "RegionA"
                prefix 1.1.1.0/24 prefix-length-range 32-32
            exit
            policy-statement "PS_OSPF_LDP_EXP_RA"
                entry 10
                    from
                        prefix-list "RegionA"
                    exit
                    action accept
                    exit
                exit
                default-action reject
            exit
            commit
        exit
        ospf
            asbr
            export "PS_OSPF_LDP_EXP_RA"
        exit
        ldp
            export-tunnel-table "PS_OSPF_LDP_EXP_RA"
        exit
    exit
exit all

Remember: SROS specifically requires OSPF in the GRT to be defined as an ASBR if you intend to export routes.

A:RA-2# show router tunnel-table

===============================================================================
Tunnel Table (Router: Base)
===============================================================================
Destination           Owner Encap TunnelId  Pref     Nexthop        Metric
-------------------------------------------------------------------------------
1.1.1.1/32            ldp   MPLS   -        9        1.1.2.1        100
1.1.1.3/32            ldp   MPLS   -        9        1.2.3.3        100
2.2.2.1/32            ldp   MPLS   -        9        1.1.2.1        1
2.2.2.2/32            ldp   MPLS   -        9        1.1.2.1        1
2.2.2.3/32            ldp   MPLS   -        9        1.1.2.1        1
-------------------------------------------------------------------------------
Flags: B = BGP backup route available
E = inactive best-external BGP route
===============================================================================
A:RA-3# show router tunnel-table

===============================================================================
Tunnel Table (Router: Base)
===============================================================================
Destination           Owner Encap TunnelId  Pref     Nexthop        Metric
-------------------------------------------------------------------------------
1.1.1.1/32            ldp   MPLS   -        9        1.1.3.1        100
1.1.1.2/32            ldp   MPLS   -        9        1.2.3.2        100
2.2.2.1/32            ldp   MPLS   -        9        1.1.3.1        1
2.2.2.2/32            ldp   MPLS   -        9        1.1.3.1        1
2.2.2.3/32            ldp   MPLS   -        9        1.1.3.1        1
-------------------------------------------------------------------------------
Flags: B = BGP backup route available
E = inactive best-external BGP route
===============================================================================
A:RB-2# show router tunnel-table

===============================================================================
IPv4 Tunnel Table (Router: Base)
===============================================================================
Destination       Owner     Encap TunnelId  Pref     Nexthop        Metric
-------------------------------------------------------------------------------
1.1.1.1/32        ldp       MPLS  65619     9        2.1.2.1        1
1.1.1.2/32        ldp       MPLS  65620     9        2.1.2.1        1
1.1.1.3/32        ldp       MPLS  65621     9        2.1.2.1        1
2.2.2.1/32        ldp       MPLS  65596     9        2.1.2.1        100
2.2.2.3/32        ldp       MPLS  65544     9        2.2.3.3        100
-------------------------------------------------------------------------------
Flags: B = BGP backup route available
E = inactive best-external BGP route
===============================================================================
A:RB-3# show router tunnel-table

===============================================================================
IPv4 Tunnel Table (Router: Base)
===============================================================================
Destination       Owner     Encap TunnelId  Pref     Nexthop        Metric
-------------------------------------------------------------------------------
1.1.1.1/32        ldp       MPLS  65620     9        2.1.3.1        1
1.1.1.2/32        ldp       MPLS  65621     9        2.1.3.1        1
1.1.1.3/32        ldp       MPLS  65622     9        2.1.3.1        1
2.2.2.1/32        ldp       MPLS  65597     9        2.1.3.1        100
2.2.2.2/32        ldp       MPLS  65537     9        2.2.3.2        100
-------------------------------------------------------------------------------
Flags: B = BGP backup route available
E = inactive best-external BGP route
===============================================================================

Okay, we have tunnels between all routers in both Regions A and B.
The final step to get VPRN connectivity between Region A and Region B is to peer the VPN Route Reflectors (RA-3 and RB-3)

configure
    router
        bgp
            group "VPN-RR-RegionB"
                family vpn-ipv4
                peer-as 65000
                neighbor 2.2.2.3
                    description "RB-3"
                exit
            exit
        exit
    exit all
configure
    router
        bgp
            group "VPN-RR-RegionA"
                family vpn-ipv4
                peer-as 65000
                neighbor 1.1.1.3
                    description "RA-3"
                exit
            exit
        exit
    exit all

We should be able to now verify this with VPRN 123

A:RA-1# show router 123 route-table

===============================================================================
Route Table (Service: 123)
===============================================================================
Dest Prefix[Flags]                            Type    Proto     Age        Pref
    Next Hop[Interface Name]                                    Metric
-------------------------------------------------------------------------------
123.1.1.1/32                                  Local   Local     00h50m13s  0
    Loop                                                         0
123.1.1.2/32                                  Remote  BGP VPN   00h44m50s  170
    1.1.1.2 (tunneled)                                           0
123.1.1.3/32                                  Remote  BGP VPN   00h45m49s  170
    1.1.1.3 (tunneled)                                           0
123.2.2.1/32                                  Remote  BGP VPN   00h00m26s  170
    2.2.2.1 (tunneled:BGP)                                       0
123.2.2.2/32                                  Remote  BGP VPN   00h00m26s  170
    2.2.2.2 (tunneled:BGP)                                       0
123.2.2.3/32                                  Remote  BGP VPN   00h00m26s  170
    2.2.2.3 (tunneled:BGP)                                       0
-------------------------------------------------------------------------------
No. of Routes: 6
Flags: n = Number of times nexthop is repeated
B = BGP backup route available
L = LFA nexthop available
S = Sticky ECMP requested
===============================================================================
A:RA-1# ping router 123 123.1.1.1 count 1
PING 123.1.1.1 56 data bytes
64 bytes from 123.1.1.1: icmp_seq=1 ttl=64 time=0.245ms.

---- 123.1.1.1 PING Statistics ----
1 packet transmitted, 1 packet received, 0.00% packet loss
round-trip min = 0.245ms, avg = 0.245ms, max = 0.245ms, stddev = 0.000ms
A:RA-1# ping router 123 123.1.1.2 count 1
PING 123.1.1.2 56 data bytes
64 bytes from 123.1.1.2: icmp_seq=1 ttl=64 time=1.26ms.

---- 123.1.1.2 PING Statistics ----
1 packet transmitted, 1 packet received, 0.00% packet loss
round-trip min = 1.26ms, avg = 1.26ms, max = 1.26ms, stddev = 0.000ms
A:RA-1# ping router 123 123.1.1.3 count 1
PING 123.1.1.3 56 data bytes
64 bytes from 123.1.1.3: icmp_seq=1 ttl=64 time=1.37ms.

---- 123.1.1.3 PING Statistics ----
1 packet transmitted, 1 packet received, 0.00% packet loss
round-trip min = 1.37ms, avg = 1.37ms, max = 1.37ms, stddev = 0.000ms
A:RA-1# ping router 123 123.2.2.1 count 1
PING 123.2.2.1 56 data bytes
64 bytes from 123.2.2.1: icmp_seq=1 ttl=64 time=3.46ms.

---- 123.2.2.1 PING Statistics ----
1 packet transmitted, 1 packet received, 0.00% packet loss
round-trip min = 3.46ms, avg = 3.46ms, max = 3.46ms, stddev = 0.000ms
A:RA-1# ping router 123 123.2.2.2 count 1
PING 123.2.2.2 56 data bytes
64 bytes from 123.2.2.2: icmp_seq=1 ttl=64 time=3.92ms.

---- 123.2.2.2 PING Statistics ----
1 packet transmitted, 1 packet received, 0.00% packet loss
round-trip min = 3.92ms, avg = 3.92ms, max = 3.92ms, stddev = 0.000ms
A:RA-1# ping router 123 123.2.2.3 count 1
PING 123.2.2.3 56 data bytes
64 bytes from 123.2.2.3: icmp_seq=1 ttl=64 time=3.83ms.

---- 123.2.2.3 PING Statistics ----
1 packet transmitted, 1 packet received, 0.00% packet loss
round-trip min = 3.83ms, avg = 3.83ms, max = 3.83ms, stddev = 0.000ms
A:RA-2# show router 123 route-table

===============================================================================
Route Table (Service: 123)
===============================================================================
Dest Prefix[Flags]                            Type    Proto     Age        Pref
    Next Hop[Interface Name]                                    Metric
-------------------------------------------------------------------------------
123.1.1.1/32                                  Remote  BGP VPN   00h46m12s  170
    1.1.1.1 (tunneled)                                           0
123.1.1.2/32                                  Local   Local     00h48m34s  0
    Loop                                                         0
123.1.1.3/32                                  Remote  BGP VPN   00h46m12s  170
    1.1.1.3 (tunneled)                                           0
123.2.2.1/32                                  Remote  BGP VPN   00h01m31s  170
    2.2.2.1 (tunneled)                                           0
123.2.2.2/32                                  Remote  BGP VPN   00h01m31s  170
    2.2.2.2 (tunneled)                                           0
123.2.2.3/32                                  Remote  BGP VPN   00h01m31s  170
    2.2.2.3 (tunneled)                                           0
-------------------------------------------------------------------------------
No. of Routes: 6
Flags: n = Number of times nexthop is repeated
B = BGP backup route available
L = LFA nexthop available
S = Sticky ECMP requested
===============================================================================
A:RA-2# ping router 123 123.1.1.1 count 1
PING 123.1.1.1 56 data bytes
64 bytes from 123.1.1.1: icmp_seq=1 ttl=64 time=1.12ms.

---- 123.1.1.1 PING Statistics ----
1 packet transmitted, 1 packet received, 0.00% packet loss
round-trip min = 1.12ms, avg = 1.12ms, max = 1.12ms, stddev = 0.000ms
A:RA-2# ping router 123 123.1.1.2 count 1
PING 123.1.1.2 56 data bytes
64 bytes from 123.1.1.2: icmp_seq=1 ttl=64 time=0.171ms.

---- 123.1.1.2 PING Statistics ----
1 packet transmitted, 1 packet received, 0.00% packet loss
round-trip min = 0.171ms, avg = 0.171ms, max = 0.171ms, stddev = 0.000ms
A:RA-2# ping router 123 123.1.1.3 count 1
PING 123.1.1.3 56 data bytes
64 bytes from 123.1.1.3: icmp_seq=1 ttl=64 time=1.31ms.

---- 123.1.1.3 PING Statistics ----
1 packet transmitted, 1 packet received, 0.00% packet loss
round-trip min = 1.31ms, avg = 1.31ms, max = 1.31ms, stddev = 0.000ms
A:RA-2# ping router 123 123.2.2.1 count 1
PING 123.2.2.1 56 data bytes
64 bytes from 123.2.2.1: icmp_seq=1 ttl=64 time=4.12ms.

---- 123.2.2.1 PING Statistics ----
1 packet transmitted, 1 packet received, 0.00% packet loss
round-trip min = 4.12ms, avg = 4.12ms, max = 4.12ms, stddev = 0.000ms
A:RA-2# ping router 123 123.2.2.2 count 1
PING 123.2.2.2 56 data bytes
64 bytes from 123.2.2.2: icmp_seq=1 ttl=64 time=7.76ms.

---- 123.2.2.2 PING Statistics ----
1 packet transmitted, 1 packet received, 0.00% packet loss
round-trip min = 7.76ms, avg = 7.76ms, max = 7.76ms, stddev = 0.000ms
A:RA-2# ping router 123 123.2.2.3 count 1
PING 123.2.2.3 56 data bytes
64 bytes from 123.2.2.3: icmp_seq=1 ttl=64 time=4.53ms.

---- 123.2.2.3 PING Statistics ----
1 packet transmitted, 1 packet received, 0.00% packet loss
round-trip min = 4.53ms, avg = 4.53ms, max = 4.53ms, stddev = 0.000ms
A:RA-3# show router 123 route-table

===============================================================================
Route Table (Service: 123)
===============================================================================
Dest Prefix[Flags]                            Type    Proto     Age        Pref
    Next Hop[Interface Name]                                    Metric
-------------------------------------------------------------------------------
123.1.1.1/32                                  Remote  BGP VPN   00h47m48s  170
    1.1.1.1 (tunneled)                                           0
123.1.1.2/32                                  Remote  BGP VPN   00h46m56s  170
    1.1.1.2 (tunneled)                                           0
123.1.1.3/32                                  Local   Local     00h49m05s  0
    Loop                                                         0
123.2.2.1/32                                  Remote  BGP VPN   00h02m37s  170
    2.2.2.1 (tunneled)                                           0
123.2.2.2/32                                  Remote  BGP VPN   00h02m37s  170
    2.2.2.2 (tunneled)                                           0
123.2.2.3/32                                  Remote  BGP VPN   00h02m37s  170
    2.2.2.3 (tunneled)                                           0
-------------------------------------------------------------------------------
No. of Routes: 6
Flags: n = Number of times nexthop is repeated
B = BGP backup route available
L = LFA nexthop available
S = Sticky ECMP requested
===============================================================================
A:RA-3>config>router# ping router 123 123.1.1.1 count 1
PING 123.1.1.1 56 data bytes
64 bytes from 123.1.1.1: icmp_seq=1 ttl=64 time=1.17ms.

---- 123.1.1.1 PING Statistics ----
1 packet transmitted, 1 packet received, 0.00% packet loss
round-trip min = 1.17ms, avg = 1.17ms, max = 1.17ms, stddev = 0.000ms
A:RA-3>config>router# ping router 123 123.1.1.2 count 1
PING 123.1.1.2 56 data bytes
64 bytes from 123.1.1.2: icmp_seq=1 ttl=64 time=1.07ms.

---- 123.1.1.2 PING Statistics ----
1 packet transmitted, 1 packet received, 0.00% packet loss
round-trip min = 1.07ms, avg = 1.07ms, max = 1.07ms, stddev = 0.000ms
A:RA-3>config>router# ping router 123 123.1.1.3 count 1
PING 123.1.1.3 56 data bytes
64 bytes from 123.1.1.3: icmp_seq=1 ttl=64 time=0.166ms.

---- 123.1.1.3 PING Statistics ----
1 packet transmitted, 1 packet received, 0.00% packet loss
round-trip min = 0.166ms, avg = 0.166ms, max = 0.166ms, stddev = 0.000ms
A:RA-3>config>router# ping router 123 123.2.2.1 count 1
PING 123.2.2.1 56 data bytes
64 bytes from 123.2.2.1: icmp_seq=1 ttl=64 time=6.13ms.

---- 123.2.2.1 PING Statistics ----
1 packet transmitted, 1 packet received, 0.00% packet loss
round-trip min = 6.13ms, avg = 6.13ms, max = 6.13ms, stddev = 0.000ms
A:RA-3>config>router# ping router 123 123.2.2.2 count 1
PING 123.2.2.2 56 data bytes
64 bytes from 123.2.2.2: icmp_seq=1 ttl=64 time=5.04ms.

---- 123.2.2.2 PING Statistics ----
1 packet transmitted, 1 packet received, 0.00% packet loss
round-trip min = 5.04ms, avg = 5.04ms, max = 5.04ms, stddev = 0.000ms
A:RA-3>config>router# ping router 123 123.2.2.3 count 1
PING 123.2.2.3 56 data bytes
64 bytes from 123.2.2.3: icmp_seq=1 ttl=64 time=4.37ms.

---- 123.2.2.3 PING Statistics ----
1 packet transmitted, 1 packet received, 0.00% packet loss
round-trip min = 4.37ms, avg = 4.37ms, max = 4.37ms, stddev = 0.000ms
A:RB-1# show router 123 route-table

===============================================================================
Route Table (Service: 123)
===============================================================================
Dest Prefix[Flags]                            Type    Proto     Age        Pref
    Next Hop[Interface Name]                                    Metric
-------------------------------------------------------------------------------
123.1.1.1/32                                  Remote  BGP VPN   00h03m33s  170
    1.1.1.1 (tunneled:BGP)                                       0
123.1.1.2/32                                  Remote  BGP VPN   00h03m33s  170
    1.1.1.2 (tunneled:BGP)                                       0
123.1.1.3/32                                  Remote  BGP VPN   00h03m33s  170
    1.1.1.3 (tunneled:BGP)                                       0
123.2.2.1/32                                  Local   Local     02h35m54s  0
    Loop                                                         0
123.2.2.2/32                                  Remote  BGP VPN   02h11m21s  170
    2.2.2.2 (tunneled)                                           0
123.2.2.3/32                                  Remote  BGP VPN   02h11m21s  170
    2.2.2.3 (tunneled)                                           0
-------------------------------------------------------------------------------
No. of Routes: 6
Flags: n = Number of times nexthop is repeated
B = BGP backup route available
L = LFA nexthop available
S = Sticky ECMP requested
===============================================================================
A:RB-1# ping router 123 123.1.1.1 count 1
PING 123.1.1.1 56 data bytes
64 bytes from 123.1.1.1: icmp_seq=1 ttl=64 time=4.42ms.

---- 123.1.1.1 PING Statistics ----
1 packet transmitted, 1 packet received, 0.00% packet loss
round-trip min = 4.42ms, avg = 4.42ms, max = 4.42ms, stddev = 0.000ms
A:RB-1# ping router 123 123.1.1.2 count 1
PING 123.1.1.2 56 data bytes
64 bytes from 123.1.1.2: icmp_seq=1 ttl=64 time=3.89ms.

---- 123.1.1.2 PING Statistics ----
1 packet transmitted, 1 packet received, 0.00% packet loss
round-trip min = 3.89ms, avg = 3.89ms, max = 3.89ms, stddev = 0.000ms
A:RB-1# ping router 123 123.1.1.3 count 1
PING 123.1.1.3 56 data bytes
64 bytes from 123.1.1.3: icmp_seq=1 ttl=64 time=5.97ms.

---- 123.1.1.3 PING Statistics ----
1 packet transmitted, 1 packet received, 0.00% packet loss
round-trip min = 5.97ms, avg = 5.97ms, max = 5.97ms, stddev = 0.000ms
A:RB-1# ping router 123 123.2.2.1 count 1
PING 123.2.2.1 56 data bytes
64 bytes from 123.2.2.1: icmp_seq=1 ttl=64 time=0.118ms.

---- 123.2.2.1 PING Statistics ----
1 packet transmitted, 1 packet received, 0.00% packet loss
round-trip min = 0.118ms, avg = 0.118ms, max = 0.118ms, stddev = 0.000ms
A:RB-1# ping router 123 123.2.2.2 count 1
PING 123.2.2.2 56 data bytes
64 bytes from 123.2.2.2: icmp_seq=1 ttl=64 time=1.96ms.

---- 123.2.2.2 PING Statistics ----
1 packet transmitted, 1 packet received, 0.00% packet loss
round-trip min = 1.96ms, avg = 1.96ms, max = 1.96ms, stddev = 0.000ms
A:RB-1# ping router 123 123.2.2.3 count 1
PING 123.2.2.3 56 data bytes
64 bytes from 123.2.2.3: icmp_seq=1 ttl=64 time=1.80ms.

---- 123.2.2.3 PING Statistics ----
1 packet transmitted, 1 packet received, 0.00% packet loss
round-trip min = 1.80ms, avg = 1.80ms, max = 1.80ms, stddev = 0.000ms
A:RB-2# show router 123 route-table

===============================================================================
Route Table (Service: 123)
===============================================================================
Dest Prefix[Flags]                            Type    Proto     Age        Pref
    Next Hop[Interface Name]                                    Metric
-------------------------------------------------------------------------------
123.1.1.1/32                                  Remote  BGP VPN   00h04m13s  170
    1.1.1.1 (tunneled)                                           0
123.1.1.2/32                                  Remote  BGP VPN   00h04m13s  170
    1.1.1.2 (tunneled)                                           0
123.1.1.3/32                                  Remote  BGP VPN   00h04m13s  170
    1.1.1.3 (tunneled)                                           0
123.2.2.1/32                                  Remote  BGP VPN   02h11m55s  170
    2.2.2.1 (tunneled)                                           0
123.2.2.2/32                                  Local   Local     03h04m35s  0
    Loop                                                         0
123.2.2.3/32                                  Remote  BGP VPN   02h36m00s  170
    2.2.2.3 (tunneled)                                           0
-------------------------------------------------------------------------------
No. of Routes: 6
Flags: n = Number of times nexthop is repeated
B = BGP backup route available
L = LFA nexthop available
S = Sticky ECMP requested
===============================================================================
A:RB-2# ping router 123 123.1.1.1 count 1
PING 123.1.1.1 56 data bytes
64 bytes from 123.1.1.1: icmp_seq=1 ttl=64 time=3.43ms.

---- 123.1.1.1 PING Statistics ----
1 packet transmitted, 1 packet received, 0.00% packet loss
round-trip min = 3.43ms, avg = 3.43ms, max = 3.43ms, stddev = 0.000ms
A:RB-2# ping router 123 123.1.1.2 count 1
PING 123.1.1.2 56 data bytes
64 bytes from 123.1.1.2: icmp_seq=1 ttl=64 time=5.63ms.

---- 123.1.1.2 PING Statistics ----
1 packet transmitted, 1 packet received, 0.00% packet loss
round-trip min = 5.63ms, avg = 5.63ms, max = 5.63ms, stddev = 0.000ms
A:RB-2# ping router 123 123.1.1.3 count 1
PING 123.1.1.3 56 data bytes
64 bytes from 123.1.1.3: icmp_seq=1 ttl=64 time=4.40ms.

---- 123.1.1.3 PING Statistics ----
1 packet transmitted, 1 packet received, 0.00% packet loss
round-trip min = 4.40ms, avg = 4.40ms, max = 4.40ms, stddev = 0.000ms
A:RB-2# ping router 123 123.2.2.1 count 1
PING 123.2.2.1 56 data bytes
64 bytes from 123.2.2.1: icmp_seq=1 ttl=64 time=1.85ms.

---- 123.2.2.1 PING Statistics ----
1 packet transmitted, 1 packet received, 0.00% packet loss
round-trip min = 1.85ms, avg = 1.85ms, max = 1.85ms, stddev = 0.000ms
A:RB-2# ping router 123 123.2.2.2 count 1
PING 123.2.2.2 56 data bytes
64 bytes from 123.2.2.2: icmp_seq=1 ttl=64 time=0.150ms.

---- 123.2.2.2 PING Statistics ----
1 packet transmitted, 1 packet received, 0.00% packet loss
round-trip min = 0.150ms, avg = 0.150ms, max = 0.150ms, stddev = 0.000ms
A:RB-2# ping router 123 123.2.2.3 count 1
PING 123.2.2.3 56 data bytes
64 bytes from 123.2.2.3: icmp_seq=1 ttl=64 time=1.90ms.

---- 123.2.2.3 PING Statistics ----
1 packet transmitted, 1 packet received, 0.00% packet loss
round-trip min = 1.90ms, avg = 1.90ms, max = 1.90ms, stddev = 0.000ms
A:RB-3# show router 123 route-table

===============================================================================
Route Table (Service: 123)
===============================================================================
Dest Prefix[Flags]                            Type    Proto     Age        Pref
    Next Hop[Interface Name]                                    Metric
-------------------------------------------------------------------------------
123.1.1.1/32                                  Remote  BGP VPN   00h05m23s  170
    1.1.1.1 (tunneled)                                           0
123.1.1.2/32                                  Remote  BGP VPN   00h05m23s  170
    1.1.1.2 (tunneled)                                           0
123.1.1.3/32                                  Remote  BGP VPN   00h05m23s  170
    1.1.1.3 (tunneled)                                           0
123.2.2.1/32                                  Remote  BGP VPN   02h13m05s  170
    2.2.2.1 (tunneled)                                           0
123.2.2.2/32                                  Remote  BGP VPN   02h37m03s  170
    2.2.2.2 (tunneled)                                           0
123.2.2.3/32                                  Local   Local     02h37m07s  0
    Loop                                                         0
-------------------------------------------------------------------------------
No. of Routes: 6
Flags: n = Number of times nexthop is repeated
B = BGP backup route available
L = LFA nexthop available
S = Sticky ECMP requested
===============================================================================
A:RB-3# ping router 123 123.1.1.1 count 1
PING 123.1.1.1 56 data bytes
64 bytes from 123.1.1.1: icmp_seq=1 ttl=64 time=3.83ms.

---- 123.1.1.1 PING Statistics ----
1 packet transmitted, 1 packet received, 0.00% packet loss
round-trip min = 3.83ms, avg = 3.83ms, max = 3.83ms, stddev = 0.000ms
A:RB-3# ping router 123 123.1.1.2 count 1
PING 123.1.1.2 56 data bytes
64 bytes from 123.1.1.2: icmp_seq=1 ttl=64 time=4.38ms.

---- 123.1.1.2 PING Statistics ----
1 packet transmitted, 1 packet received, 0.00% packet loss
round-trip min = 4.38ms, avg = 4.38ms, max = 4.38ms, stddev = 0.000ms
A:RB-3# ping router 123 123.1.1.3 count 1
PING 123.1.1.3 56 data bytes
64 bytes from 123.1.1.3: icmp_seq=1 ttl=64 time=4.47ms.

---- 123.1.1.3 PING Statistics ----
1 packet transmitted, 1 packet received, 0.00% packet loss
round-trip min = 4.47ms, avg = 4.47ms, max = 4.47ms, stddev = 0.000ms
A:RB-3# ping router 123 123.2.2.1 count 1
PING 123.2.2.1 56 data bytes
64 bytes from 123.2.2.1: icmp_seq=1 ttl=64 time=1.97ms.

---- 123.2.2.1 PING Statistics ----
1 packet transmitted, 1 packet received, 0.00% packet loss
round-trip min = 1.97ms, avg = 1.97ms, max = 1.97ms, stddev = 0.000ms
A:RB-3# ping router 123 123.2.2.2 count 1
PING 123.2.2.2 56 data bytes
64 bytes from 123.2.2.2: icmp_seq=1 ttl=64 time=1.88ms.

---- 123.2.2.2 PING Statistics ----
1 packet transmitted, 1 packet received, 0.00% packet loss
round-trip min = 1.88ms, avg = 1.88ms, max = 1.88ms, stddev = 0.000ms
A:RB-3# ping router 123 123.2.2.3 count 1
PING 123.2.2.3 56 data bytes
64 bytes from 123.2.2.3: icmp_seq=1 ttl=64 time=0.269ms.

---- 123.2.2.3 PING Statistics ----
1 packet transmitted, 1 packet received, 0.00% packet loss
round-trip min = 0.269ms, avg = 0.269ms, max = 0.269ms, stddev = 0.000ms

While this is quite a long post, the actual configuration itself for the CSC is straight forward:

  • The CSC VPRN must be set to carrier-carrier-vpn
  • The CSC VPRN uses Ethernet ports with mode network even though its for customers
  • The CSC-PE and CSC-CE exchange labeled routes
  • The CSC-CE redistributes between OSPF/LDP and BGP

Changes to the way the RIB works on SROS and how that impacts CsC configurations was also briefly discussed.