CCNP ROUTE: 7. IPv6 static routes

Syntax:

ipv6 route prefix/length {outgoing-interface [next-hop-address] | next-hopaddress} [admin-distance] [tag tag-value]

Differences between IPv4 and IPv6 static routes:

- First, when using the next-hop IP address, you can use any address on the neighboring router, including the neighbor’s link local IPv6 address.
- Second, if using a link local address as the next-hop address, then you must configure both the outgoing interface and the link local address.

Let's consider routers R5, R2 and R3.
R5 wants to reach R3's Fa0/0 interface:

R3#show ipv6 interface fastEthernet 0/0
FastEthernet0/0 is up, line protocol is up
  IPv6 is enabled, link-local address is FE80::C203:12FF:FE0C:0
  Global unicast address(es):
    2000:0:0:3::2, subnet is 2000:0:0:3::/64
   
R5#ping 2000:0:0:3::2

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 2000:0:0:3::2, timeout is 2 seconds:
.....
Success rate is 0 percent (0/5)

No routing protocol is configured between the two routers, so R5 does not have a route to the destination subnet and R3 does not have a route back to R5's subnet (2001::/64).

R5#show ipv6 route
...
C   2001::/64 [0/0]
     via ::, FastEthernet0/0
L   2001::C204:13FF:FEE8:0/128 [0/0]
     via ::, FastEthernet0/0
L   FE80::/10 [0/0]
     via ::, Null0
L   FF00::/8 [0/0]
     via ::, Null0

R3#show ipv6 route
...
C   2000:0:0:2::/64 [0/0]
     via ::, FastEthernet0/1
L   2000:0:0:2::2/128 [0/0]
     via ::, FastEthernet0/1
C   2000:0:0:3::/64 [0/0]
     via ::, FastEthernet0/0
L   2000:0:0:3::2/128 [0/0]
     via ::, FastEthernet0/0
R   2002::/64 [120/2]
     via FE80::C201:12FF:FE0C:0, FastEthernet0/1
C   2003::/64 [0/0]
     via ::, Serial0/0
L   2003::1/128 [0/0]
     via ::, Serial0/0
O   2003:0:0:1::/64 [110/74]
     via FE80::C205:13FF:FEE8:0, Serial0/0
L   FE80::/10 [0/0]
     via ::, Null0
L   FF00::/8 [0/0]
     via ::, Null0

Let's configure static routes in both possible ways:

R3(config)#ipv6 route 2001::/64 2000:0:0:3::1

R5(config)#ipv6 route 2000:0:0:3::/64 fastEthernet 0/0 FE80::C202:12FF:FE0C:0

...where FE80::C202:12FF:FE0C:0 is R2's Fa0/0 link local address.

R2#show ipv6 interface brief fastEthernet 0/0
FastEthernet0/0            [up/up]
    FE80::C202:12FF:FE0C:0
    2001::1
   
R5#ping 2000:0:0:3::2

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 2000:0:0:3::2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 12/29/44 ms

R3#ping 2001::C204:13FF:FEE8:0

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 2001::C204:13FF:FEE8:0, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 12/24/40 ms

...where 2001::C204:13FF:FEE8:0 is R5's Fa0/0 IPv6 EUI-64 address.

Verification commands (on R5):

R5#show ipv6 route static
IPv6 Routing Table - 5 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
S   2000:0:0:3::/64 [1/0]
     via FE80::C202:12FF:FE0C:0, FastEthernet0/0