6PE Part 1

Basic IPv4/MPLS Core configuration

PE1

mpls ip
mpls label proto ldp
!
int lo0
ip add 1.1.1.1 255.255.255.255
ip ospf 1 area 0
!
int fa1/0
ip add 10.1.5.1 255.255.255.0
mpls ip
ip ospf 1 area 0
no shut

PE2

mpls ip
mpls label proto ldp
!
int lo0
ip add 2.2.2.2 255.255.255.255
ip ospf 1 area 0
!
int fa1/0
ip add 10.2.5.2 255.255.255.0
mpls ip
ip ospf 1 area 0
no shut

P1

mpls ip
mpls label proto ldp
!
int lo0
ip add 5.5.5.5 255.255.255.255
ip ospf 1 area 0
!
int fa1/0
ip add 10.1.5.5 255.255.255.0
mpls ip
ip ospf 1 area 0
no shut
!
int fa1/1
ip add 10.2.5.5 255.255.255.0
mpls ip
ip ospf 1 area 0
no shut

IPv6 edge configuration

PE1

ipv6 unicast-routing
!
int fa1/1
ipv6 add fe80::1 link-local
ipv6 add 2001:13::1/64
no shut

PE2

ipv6 unicast-routing
!
int fa1/1
ipv6 add fe80::2 link-local
ipv6 add 2001:24::2/64
no shut

CE1

ipv6 unicast-routing
!
int lo0
ipv6 add 2001:3::3/64
!
int fa1/0
ipv6 add fe80::3 link-local
ipv6 add 2001:13::3/64
no shut

CE2

ipv6 unicast-routing
!
int lo0
ipv6 add 2001:4::4/64
!
int fa1/0
ipv6 add fe80::4 link-local
ipv6 add 2001:24::4/64
no shut

Core and edge verification

Thats enough.

So now we got IPv6 islands separated by an IPv4/MPLS core. The beaty is that since we’re running MPLS we can use labels for the transport network and hence our P1 router that isn’t IPv6-enabled can still forward the IPv6 packets from PE1 to PE2.

IPv6 Configuration

We’ll use MP-BGP

PE1

router bgp 100
no auto
no sync
no bgp default ipv4-unicast
bgp router-id 1.1.1.1
neighbor 2001:13::3 remote-as 300
neighbor 2.2.2.2 remote-as 100
neighbor 2.2.2.2 upd lo0
!
address-family ipv6 unicast
neighbor 2001:13::3 activate
neighbor 2.2.2.2 activate

PE2

router bgp 100
no auto
no sync
no bgp default ipv4-unicast
bgp router-id 2.2.2.2
neighbor 2001:24::4 remote-as 400
neighbor 1.1.1.1 remote-as 100
neighbor 1.1.1.1 upd lo0
!
address-family ipv6 unicast
neighbor 2001:24::4 activate
neighbor 1.1.1.1 activate

CE1

route-map CONNECTED_TO_BGP permit 10
match int lo0
!
router bgp 300
no auto
no sync
no bgp default ipv4-unicast
bgp router-id 3.3.3.3
neighbor 2001:13::1 remote-as 100
!
adress-family ipv6 unicast
neighbor 2001:13::1 activate
redistribute connected route-map CONNECTED_TO_BGP

CE2

route-map CONNECTED_TO_BGP permit 10
match int lo0
!
router bgp 400
no auto
no sync
no bgp default ipv4-unicast
bgp router-id 4.4.4.4
neighbor 2001:24::4 remote-as 100
!
adress-family ipv6 unicast
neighbor 2001:24::2 activate
redistribute connected route-map CONNECTED_TO_BGP

Something looks strange with the remote island prefix:

Thats because we don’t now how to get to the next-hop address

We’re not using any labels, so let’s fix that

PE1

router bgp 100
address-fam ipv6 uni
neigh 2.2.2.2 send-label

PE2

router bgp 100
address-fam ipv6 uni
neigh 1.1.1.1 send-label

Now what?

We got a label

So let’s test:

Source:

6PE Part 1

January 11, 2013 by bitsandbeans