InterAS Multicast Routing

Problema pe care o analizam mai jos consta in rutarea traficului multicast intre o sursa din AS 100 si o destinatie din AS 200. Mai mult, am analizat o topologie in care Rendezvouz Point-urile (RP) sa nu fie tranzitate de traficul multicast (tot ce am gasit eu sunt scenarii cu RP pe post de bordere, deci traficul tranziteaza RP-urile - cam nerealist din punctul meu de vedere).

Cateva aspecte cheie:
- RP in AS 100 se distribuie automat prin Auto-RP, iar in AS 200 prin BSR
- intre ASBR-uri exista adiacenta PIM, dar ASBR1 filtreaza adresele IP multicast pe care se distribuie mesajele Auto-RP adica 224.0.1.39 (Auto-RP Announce) si 224.0.1.40 (Auto-RP Discovery); ASBR2 filtreaza mesajele BSR (am folosit optiunea BSR-border)
- sesiune eBGP pentru address-family IPv4 multicast intre ASBR-uri, pentru Reverse Path Forwarding (RPF)
- sesiuni iBGP pentru address-family IPv4 multicast intre ASBR-uri si routerele din fiecare AS, tot pentru RPF - aici am configurat ASBR sa fie si Route Reflector pentru AFI/SAFI 1/2 (address-family IPv4 multicast)
- OSPF este protocol IGP in fiecare AS, dar ASBR-urile nu au adiacenta OSPF intre ele, ci doar anunta o ruta implicita
- sesiune MSDP intre RP-uri ca sa isi anunte sursele si astfel sa permita traficul multicast sa porneasca de la o sursa dintr-un AS si sa ajunga la destinatiile multicast din alt AS
- FH (first-hop router) este routerul in care este direct conectat sursa traficului multicast, iar LH (last-hop router) este cel in care se conecteaza direct o destinatie multicast

Topologie

Config routerelor ASBR

ASBR 1 hostname ASBR1 ip multicast-routing interface Loopback0 ip address 1.1.1.1 255.255.255.255 !Ethernet0/0 - leg cu ASBR 2 interface Ethernet0/0 ip address 10.12.12.1 255.255.255.0 ip pim sparse-mode ip multicast boundary 1 !Ethernet0/1.121 - leg cu RP 1 interface Ethernet0/1.121 encapsulation dot1Q 121 ip address 192.168.121.1 255.255.255.0 ip pim sparse-mode !Ethernet0/1.122 - leg cu FH interface Ethernet0/1.122 encapsulation dot1Q 122 ip address 192.168.122.1 255.255.255.0 ip pim sparse-mode router ospf 1 network 1.1.1.1 0.0.0.0 area 1 network 192.168.0.0 0.0.255.255 area 0 default-information originate always router bgp 100 !sesiune eBGP cu ASBR 2 neighbor 10.12.12.2 remote-as 200 !sesiuni iBGP cu RP 1 si FH neighbor 21.21.21.21 remote-as 100 neighbor 21.21.21.21 update-source Loopback0 neighbor 22.22.22.22 remote-as 100 neighbor 22.22.22.22 update-source Loopback0 address-family ipv4 redistribute ospf 1 neighbor 10.12.12.2 activate exit-address-family address-family ipv4 multicast redistribute ospf 1 neighbor 10.12.12.2 activate neighbor 21.21.21.21 activate neighbor 21.21.21.21 route-reflector-client neighbor 22.22.22.22 activate neighbor 22.22.22.22 route-reflector-client exit-address-family access-list 1 deny 224.0.1.39 access-list 1 deny 224.0.1.40 access-list 1 permit any

ASBR 2 hostname ASBR2 ip multicast-routing interface Loopback0 ip address 2.2.2.2 255.255.255.255 !Ethernet0/1 - leg cu ASBR 1 interface Ethernet0/1 ip address 10.12.12.2 255.255.255.0 ip pim bsr-border ip pim sparse-mode !Ethernet0/0.25 - leg cu RP 2 interface Ethernet0/0.25 encapsulation dot1Q 25 ip address 172.16.25.2 255.255.255.0 ip pim sparse-mode !Ethernet0/0.26 - leg cu LH interface Ethernet0/0.26 encapsulation dot1Q 26 ip address 172.16.26.2 255.255.255.0 ip pim sparse-mode router ospf 1 network 2.2.2.2 0.0.0.0 area 2 network 172.16.0.0 0.0.255.255 area 0 default-information originate always router bgp 200 !sesiune eBGP cu ASBR 1 neighbor 10.12.12.1 remote-as 100 !sesiuni iBGP cu RP 2 si LH neighbor 5.5.5.5 remote-as 200 neighbor 5.5.5.5 update-source Loopback0 neighbor 6.6.6.6 remote-as 200 neighbor 6.6.6.6 update-source Loopback0 address-family ipv4 redistribute ospf 1 neighbor 10.12.12.1 activate exit-address-family address-family ipv4 multicast redistribute ospf 1 neighbor 5.5.5.5 activate neighbor 5.5.5.5 route-reflector-client neighbor 6.6.6.6 activate neighbor 6.6.6.6 route-reflector-client neighbor 10.12.12.1 activate exit-address-family

Config routerelor RP

RP 1 hostname RP1 ip multicast-routing interface Loopback0 ip address 21.21.21.21 255.255.255.255 ip pim sparse-mode !Ethernet0/0.121 - leg cu ASBR 1 interface Ethernet0/0.121 encapsulation dot1Q 121 ip address 192.168.121.21 255.255.255.0 ip pim sparse-mode !Ethernet0/0.2122 - leg cu FH interface Ethernet0/0.2122 encapsulation dot1Q 2122 ip address 192.168.0.21 255.255.255.0 ip pim sparse-mode router ospf 1 network 21.21.21.21 0.0.0.0 area 21 network 192.168.0.0 0.0.255.255 area 0 router bgp 100 !iBGP cu ASBR 1 neighbor 1.1.1.1 remote-as 100 neighbor 1.1.1.1 update-source Loopback0 address-family ipv4 multicast neighbor 1.1.1.1 activate exit-address-family !Auto-RP ip pim send-rp-announce Loopback0 scope 3 ip pim send-rp-discovery Loopback0 scope 3 !sesiune MSDP cu RP 2 ip msdp peer 5.5.5.5 connect-source Loopback0 remote-as 200

RP 2 hostname RP2 ip multicast-routing interface Loopback0 ip address 5.5.5.5 255.255.255.255 ip pim sparse-mode !Ethernet0/0.25 - leg cu ASBR 2 interface Ethernet0/0.25 encapsulation dot1Q 25 ip address 172.16.25.5 255.255.255.0 ip pim sparse-mode !Ethernet0/0.56 - leg cu LH interface Ethernet0/0.56 encapsulation dot1Q 56 ip address 172.16.56.5 255.255.255.0 ip pim sparse-mode router ospf 1 network 5.5.5.5 0.0.0.0 area 5 network 172.16.0.0 0.0.255.255 area 0 router bgp 200 !iBGP cu ASBR 2 neighbor 2.2.2.2 remote-as 200 neighbor 2.2.2.2 update-source Loopback0 address-family ipv4 multicast neighbor 2.2.2.2 activate exit-address-family !BSR ip pim bsr-candidate Loopback0 ip pim rp-candidate Loopback0 !sesiune MSDP cu RP 1 ip msdp peer 21.21.21.21 connect-source Loopback0 remote-as 100

Config routerelor FH si LH

FH hostname FH ip multicast-routing interface Loopback0 ip address 22.22.22.22 255.255.255.255 ip pim sparse-mode !Ethernet0/0.22 - LAN cu sursa Mcast interface Ethernet0/0.22 encapsulation dot1Q 22 ip address 192.168.22.22 255.255.255.0 ip pim sparse-mode !Ethernet0/0.122 - leg cu ASBR 1 interface Ethernet0/0.122 encapsulation dot1Q 122 ip address 192.168.122.22 255.255.255.0 ip pim sparse-mode !Ethernet0/0.2122 - leg cu RP 1 interface Ethernet0/0.2122 encapsulation dot1Q 2122 ip address 192.168.0.22 255.255.255.0 ip pim sparse-mode router ospf 1 network 22.22.22.22 0.0.0.0 area 22 network 192.168.0.0 0.0.255.255 area 0 router bgp 100 !iBGP cu ASBR 1 neighbor 1.1.1.1 remote-as 200 neighbor 1.1.1.1 update-source Loopback0 address-family ipv4 multicast neighbor 1.1.1.1 activate exit-address-family

LH hostname LH ip multicast-routing interface Loopback0 ip address 6.6.6.6 255.255.255.255 ip pim sparse-mode !Ethernet0/0.6 - LAN cu destinatia Mcast interface Ethernet0/0.6 encapsulation dot1Q 6 ip address 172.16.6.6 255.255.255.0 ip pim sparse-mode ip igmp join-group 226.6.6.6 !Ethernet0/0.26 - leg cu ASBR 2 interface Ethernet0/0.26 encapsulation dot1Q 26 ip address 172.16.26.6 255.255.255.0 ip pim sparse-mode !Ethernet0/0.56 - leg cu RP 2 interface Ethernet0/0.56 encapsulation dot1Q 56 ip address 172.16.56.6 255.255.255.0 ip pim sparse-mode router ospf 1 network 6.6.6.6 0.0.0.0 area 6 network 172.16.0.0 0.0.255.255 area 0 router bgp 200 !iBGP cu ASBR 2 neighbor 2.2.2.2 remote-as 200 neighbor 2.2.2.2 update-source Loopback0 address-family ipv4 multicast neighbor 2.2.2.2 activate exit-address-family

Ca sa testati, din consola routerului FH introduceti comanda ping 226.6.6.6 source eth0/0.22 repeat 11.

Pe cei dornici sa afle mai multe ii astept la cursurile academiei Cisco Netschool.