Monday, 29 October 2012

IPv6: Tunnelling over IPv4: Tunnel mode: ipv6ip


IPv6: Tunnelling over IPv4: Tunnel mode: ipv6ip

·         Let me take a small topology to configure IPV6 tunneling over IPv4.

·         OSPFv3 is configured between R1 & R2 and R3 & R4
·         IPv4 is configured between R2-R3
·         If I need to connect R1 and R4’s IPv6 network, then I need to tunnel the IPv6 traffic through IPv4.
 
Configs:
 
R1#show run int fa0/0
Building configuration...
 
Current configuration : 134 bytes
!
interface FastEthernet0/0
 no ip address
 duplex auto
 speed auto
 ipv6 address 2001:12::1/64
 ipv6 enable
 ipv6 ospf 1 area 0
end
 
R1#show run int loop0
Building configuration...
 
Current configuration : 89 bytes
!
interface Loopback0
 no ip address
 ipv6 address 2001:1::1/64
 ipv6 ospf 1 area 0
end
 
R1#
 
R2(config-if)#do show run int fa0/0
Building configuration...
 
Current configuration : 134 bytes
!
interface FastEthernet0/0
 no ip address
 duplex auto
 speed auto
 ipv6 address 2001:12::2/64
 ipv6 enable
 ipv6 ospf 1 area 0
end
 
R2(config-if)#
 
R1#show ipv6 ospf neighbor
 
Neighbor ID     Pri   State           Dead Time   Interface ID    Interface
2.2.2.2           1   FULL/DR         00:00:38    4               FastEthernet0/0
R1#
 
R2(config-if)#do show ipv6 ospf nei
 
Neighbor ID     Pri   State           Dead Time   Interface ID    Interface
1.1.1.1           1   FULL/BDR        00:00:38    4               FastEthernet0/0
R2(config-if)#
 
R3(config-if)#do show run int fa0/0
Building configuration...
 
Current configuration : 121 bytes
!
interface FastEthernet0/0
 no ip address
 duplex auto
 speed auto
 ipv6 address 2001:34::3/64
 ipv6 ospf 1 area 0
end
 
R3(config-if)#
 
R4#show run int fa0/0
Building configuration...
 
Current configuration : 121 bytes
!
interface FastEthernet0/0
 no ip address
 duplex auto
 speed auto
 ipv6 address 2001:34::4/64
 ipv6 ospf 1 area 0
end
 
R4#show run int loop0
Building configuration...
 
Current configuration : 89 bytes
!
interface Loopback0
 no ip address
 ipv6 address 2001:4::4/64
 ipv6 ospf 1 area 0
end
 
R4#
 
R3(config-if)#do show ipv6 ospf nei
 
Neighbor ID     Pri   State           Dead Time   Interface ID    Interface
4.4.4.4           1   FULL/DR         00:00:38    4               FastEthernet0/0
R3(config-if)#
 
R4#show ipv6 ospf nei
 
Neighbor ID     Pri   State           Dead Time   Interface ID    Interface
3.3.3.3           1   FULL/BDR        00:00:31    4               FastEthernet0/0
R4#
 
Observation:
·         OSPFv3 is up between R1-R2 and R3-R4
 
·         Let me create tunnel through IPv4 to send IPv6 traffic
·         I’m going to use IPV6iIP mode for the tunnel
·         IPV6IP mode uses protocol number 41 for transporting.
 
R2(config-if)#do show run int tun1
Building configuration...
 
Current configuration : 139 bytes
!
interface Tunnel1
 no ip address
 ipv6 address 2001:23::2/64
 tunnel source 2.2.2.2
 tunnel destination 3.3.3.3
 tunnel mode ipv6ip
end
 
R2(config-if)#
 
R3(config-if)#do show run int tun1
Building configuration...
 
Current configuration : 139 bytes
!
interface Tunnel1
 no ip address
 ipv6 address 2001:23::3/64
 tunnel source 3.3.3.3
 tunnel destination 2.2.2.2
 tunnel mode ipv6ip
end
 
R3(config-if)#
 
R2#show ipv6 int tun1
Tunnel1 is up, line protocol is up
  IPv6 is enabled, link-local address is FE80::202:202
  Global unicast address(es):
    2001:23::2, subnet is 2001:23::/64
  Joined group address(es):
    FF02::1
    FF02::2
    FF02::1:FF00:2
    FF02::1:FF02:202
  MTU is 1480 bytes
  ICMP error messages limited to one every 100 milliseconds
  ICMP redirects are enabled
  ND DAD is enabled, number of DAD attempts: 1
  ND reachable time is 30000 milliseconds
  Hosts use stateless autoconfig for addresses.
R2#
 
R3#show ipv6 int tun1
Tunnel1 is up, line protocol is up
  IPv6 is enabled, link-local address is FE80::303:303
  Global unicast address(es):
    2001:23::3, subnet is 2001:23::/64
  Joined group address(es):
    FF02::1
    FF02::2
    FF02::1:FF00:3
    FF02::1:FF03:303
  MTU is 1480 bytes
  ICMP error messages limited to one every 100 milliseconds
  ICMP redirects are enabled
  ND DAD is enabled, number of DAD attempts: 1
  ND reachable time is 30000 milliseconds
  Hosts use stateless autoconfig for addresses.
R3#
 
Observation:
·         Tunnel is up between R2 and R3
·         Now, let me advertise the tunnel interfaces into OSPFv3 on R2 and R3
 
R2(config)#int tunnel 1
R2(config-if)#ipv6 ospf 1 area 0
R2(config-if)#
R2(config-if)#
*Mar  1 08:58:33.053: %OSPFv3-5-ADJCHG: Process 1, Nbr 3.3.3.3 on Tunnel1 from LOADING to FULL, Loading Done
R2(config-if)#
 
R3(config)#int tunnel 1
R3(config-if)#ipv6 ospf 1 area 0
R3(config-if)#
*Mar  1 03:53:55.127: %OSPFv3-5-ADJCHG: Process 1, Nbr 2.2.2.2 on Tunnel1 from LOADING to FULL, Loading Done
R3(config-if)#
 
·         Now, let me see R1 and R4 IPV6 routing tables:
 
R1#show ipv6 route
IPv6 Routing Table - 9 entries
Codes: C - Connected, L - Local, S - Static, R - RIP, B - BGP
       U - Per-user Static route
       I1 - ISIS L1, I2 - ISIS L2, IA - ISIS interarea, IS - ISIS summary
       O - OSPF intra, OI - OSPF inter, OE1 - OSPF ext 1, OE2 - OSPF ext 2
       ON1 - OSPF NSSA ext 1, ON2 - OSPF NSSA ext 2
C   2001:1::/64 [0/0]
     via ::, Loopback0
L   2001:1::1/128 [0/0]
     via ::, Loopback0
O   2001:4::4/128 [110/11131]
     via FE80::C001:25FF:FE30:0, FastEthernet0/0
C   2001:12::/64 [0/0]
     via ::, FastEthernet0/0
L   2001:12::1/128 [0/0]
     via ::, FastEthernet0/0
O   2001:23::/64 [110/11121]
     via FE80::C001:25FF:FE30:0, FastEthernet0/0
O   2001:34::/64 [110/11131]
     via FE80::C001:25FF:FE30:0, FastEthernet0/0
L   FE80::/10 [0/0]
     via ::, Null0
L   FF00::/8 [0/0]
     via ::, Null0
R1#
 
R4#show ipv6 route
IPv6 Routing Table - 9 entries
Codes: C - Connected, L - Local, S - Static, R - RIP, B - BGP
       U - Per-user Static route
       I1 - ISIS L1, I2 - ISIS L2, IA - ISIS interarea, IS - ISIS summary
       O - OSPF intra, OI - OSPF inter, OE1 - OSPF ext 1, OE2 - OSPF ext 2
       ON1 - OSPF NSSA ext 1, ON2 - OSPF NSSA ext 2
O   2001:1::1/128 [110/11131]
     via FE80::C003:25FF:FE30:0, FastEthernet0/0
C   2001:4::/64 [0/0]
     via ::, Loopback0
L   2001:4::4/128 [0/0]
     via ::, Loopback0
O   2001:12::/64 [110/11131]
     via FE80::C003:25FF:FE30:0, FastEthernet0/0
O   2001:23::/64 [110/11121]
     via FE80::C003:25FF:FE30:0, FastEthernet0/0
C   2001:34::/64 [0/0]
     via ::, FastEthernet0/0
L   2001:34::4/128 [0/0]
     via ::, FastEthernet0/0
L   FE80::/10 [0/0]
     via ::, Null0
L   FF00::/8 [0/0]
     via ::, Null0
R4#
 
R1#ping 2001:4::4
 
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 2001:4::4, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 12/35/96 ms
R1#
 
R4#ping 2001:1::1
 
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 2001:1::1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 12/27/64 ms
R4#

1 comment:

  1. Does OSPFv3 work over automatic 6to4 ?

    ReplyDelete