L3 VPN & OSPF Sham Link

5 vEX device topology. OSPF Sham link between vEX1 & vEX5 so the VPN backbone is preferred.

https://www.juniper.net/documentation/us/en/software/junos/ospf/topics/topic-map/configuring-ospfv2-sham-links.html

EVE-NG lab import

vEX1

set interfaces ge-0/0/0 unit 0 family inet address 11.11.11.2/30
set interfaces ge-0/0/2 unit 0 family inet address 1.1.1.1/30
set interfaces ge-0/0/2 unit 0 family iso
set interfaces ge-0/0/2 unit 0 family mpls
set interfaces lo0 unit 0 family inet address 5.5.5.5/32
set interfaces lo0 unit 0 family iso address 49.0000.5555.5555.5555.00
set interfaces lo0 unit 0 family mpls
set interfaces lo0 unit 1 family inet address 222.222.222.222/32
set interfaces lo0 unit 1 family mpls
set policy-options policy-statement nhs term 1 from protocol bgp
set policy-options policy-statement nhs term 1 then next-hop self
set routing-instances customer1 instance-type vrf
set routing-instances customer1 protocols mpls interface all
set routing-instances customer1 protocols ospf area 0.0.0.0 sham-link-remote 111.111.111.111
set routing-instances customer1 protocols ospf area 0.0.0.0 interface ge-0/0/0.0
set routing-instances customer1 protocols ospf area 0.0.0.0 interface lo0.1
set routing-instances customer1 protocols ospf sham-link local 222.222.222.222
set routing-instances customer1 interface ge-0/0/0.0
set routing-instances customer1 interface lo0.1
set routing-instances customer1 route-distinguisher 5.5.5.5:1
set routing-instances customer1 vrf-target target:65530:1
set routing-options router-id 5.5.5.5
set routing-options autonomous-system 65530
set protocols bgp group int type internal
set protocols bgp group int local-address 5.5.5.5
set protocols bgp group int family inet unicast
set protocols bgp group int family inet-vpn unicast
set protocols bgp group int export nhs
set protocols bgp group int neighbor 6.6.6.6
set protocols isis interface ge-0/0/2.0
set protocols isis interface lo0.0
set protocols ldp interface ge-0/0/2.0
set protocols ldp interface lo0.0
set protocols mpls interface all

vEX2

set interfaces ge-0/0/0 unit 0 family inet address 1.1.1.2/30
set interfaces ge-0/0/0 unit 0 family iso
set interfaces ge-0/0/0 unit 0 family mpls
set interfaces ge-0/0/1 unit 0 family inet address 2.2.2.5/30
set interfaces ge-0/0/1 unit 0 family iso
set interfaces ge-0/0/1 unit 0 family mpls
set interfaces lo0 unit 0 family inet address 6.6.6.6/32
set interfaces lo0 unit 0 family iso address 49.0000.6666.6666.6666.00
set interfaces lo0 unit 0 family mpls
set policy-options policy-statement nhs term 1 from protocol bgp
set policy-options policy-statement nhs term 1 then next-hop self
set routing-options router-id 6.6.6.6
set routing-options autonomous-system 65530
set protocols bgp group int type internal
set protocols bgp group int local-address 6.6.6.6
set protocols bgp group int family inet unicast
set protocols bgp group int family inet-vpn unicast
set protocols bgp group int export nhs
set protocols bgp group int cluster 6.6.6.6
set protocols bgp group int neighbor 5.5.5.5
set protocols bgp group int neighbor 88.88.88.88
set protocols isis interface ge-0/0/0.0
set protocols isis interface ge-0/0/1.0
set protocols isis interface lo0.0
set protocols ldp interface all
set protocols mpls interface all

Core

set interfaces ge-0/0/0 unit 0 family inet address 2.2.2.6/30
set interfaces ge-0/0/0 unit 0 family iso
set interfaces ge-0/0/0 unit 0 family mpls
set interfaces ge-0/0/1 unit 0 family inet address 4.4.4.2/30
set interfaces ge-0/0/1 unit 0 family iso
set interfaces ge-0/0/1 unit 0 family mpls
set interfaces lo0 unit 0 family inet address 88.88.88.88/32
set interfaces lo0 unit 0 family iso address 49.0000.8888.8888.0000.00
set interfaces lo0 unit 0 family mpls
set policy-options policy-statement nhs term 1 from protocol bgp
set policy-options policy-statement nhs term 1 then next-hop self
set routing-options router-id 88.88.88.88
set routing-options autonomous-system 65530
set protocols bgp group int type internal
set protocols bgp group int local-address 88.88.88.88
set protocols bgp group int family inet unicast
set protocols bgp group int family inet-vpn unicast
set protocols bgp group int export nhs
set protocols bgp group int cluster 88.88.88.88
set protocols bgp group int neighbor 6.6.6.6
set protocols bgp group int neighbor 7.7.7.7
set protocols isis interface all
set protocols ldp interface all
set protocols mpls interface all

vEX4

set interfaces ge-0/0/0 unit 0 family inet address 4.4.4.1/30
set interfaces ge-0/0/0 unit 0 family iso
set interfaces ge-0/0/0 unit 0 family mpls
set interfaces ge-0/0/1 unit 0 family inet address 3.3.3.1/30
set interfaces ge-0/0/1 unit 0 family iso
set interfaces ge-0/0/1 unit 0 family mpls
set interfaces lo0 unit 0 family inet address 7.7.7.7/32
set interfaces lo0 unit 0 family iso address 49.0000.7777.7777.7777.00
set interfaces lo0 unit 0 family mpls
set policy-options policy-statement nhs term 1 from protocol bgp
set policy-options policy-statement nhs term 1 then next-hop self
set routing-options router-id 7.7.7.7
set routing-options autonomous-system 65530
set protocols bgp group int type internal
set protocols bgp group int local-address 7.7.7.7
set protocols bgp group int family inet unicast
set protocols bgp group int family inet-vpn unicast
set protocols bgp group int export nhs
set protocols bgp group int cluster 7.7.7.7
set protocols bgp group int neighbor 8.8.8.8
set protocols bgp group int neighbor 88.88.88.88
set protocols isis interface ge-0/0/0.0
set protocols isis interface ge-0/0/1.0
set protocols isis interface lo0.0
set protocols ldp interface all

vEX5

set interfaces ge-0/0/0 unit 0 family inet address 22.22.22.2/30
set interfaces ge-0/0/2 unit 0 family inet address 3.3.3.2/30
set interfaces ge-0/0/2 unit 0 family iso
set interfaces ge-0/0/2 unit 0 family mpls
set interfaces lo0 unit 0 family inet address 8.8.8.8/32
set interfaces lo0 unit 0 family iso address 49.0000.8888.8888.8888.00
set interfaces lo0 unit 0 family mpls
set interfaces lo0 unit 1 family inet address 111.111.111.111/32
set interfaces lo0 unit 1 family mpls
set policy-options policy-statement nhs term 1 from protocol bgp
set policy-options policy-statement nhs term 1 then next-hop self
set routing-instances customer1 instance-type vrf
set routing-instances customer1 protocols ospf area 0.0.0.0 sham-link-remote 222.222.222.222
set routing-instances customer1 protocols ospf area 0.0.0.0 interface ge-0/0/0.0
set routing-instances customer1 protocols ospf area 0.0.0.0 interface lo0.1
set routing-instances customer1 protocols ospf sham-link local 111.111.111.111
set routing-instances customer1 interface ge-0/0/0.0
set routing-instances customer1 interface lo0.1
set routing-instances customer1 route-distinguisher 8.8.8.8:1
set routing-instances customer1 vrf-target target:65530:1
set routing-options router-id 8.8.8.8
set routing-options autonomous-system 65530
set protocols bgp group int type internal
set protocols bgp group int local-address 8.8.8.8
set protocols bgp group int family inet unicast
set protocols bgp group int family inet-vpn unicast
set protocols bgp group int export nhs
set protocols bgp group int neighbor 7.7.7.7
set protocols isis interface ge-0/0/2.0
set protocols isis interface lo0.0
set protocols ldp interface ge-0/0/2.0
set protocols ldp interface lo0.0
set protocols mpls interface all

Sham link should now be established. Run ‘show ospf neighbor instance customer1‘ to confirm.

root> show ospf neighbor instance customer1    
Address          Interface              State           ID               Pri  Dead
11.11.11.1       ge-0/0/0.0             Full            12.12.12.1         1    31
111.111.111.111  shamlink.0             Full            111.111.111.111    0    37