OSPF Cisco IOS/NSSA
From Teknologisk videncenter
The following topology is configured on GNS3 on Cisco 7200 Routers
The Routers have the following configuration:
R1 & R2
| R1 | R2 |
|---|---|
R1#<input>show run</input>
hostname R1
!
ipv6 unicast-routing
!
interface Loopback0
ipv6 address 2001::1/128
ipv6 ospf 1 area 0
!
interface FastEthernet0/0
ipv6 enable
ipv6 ospf 1 area 0
!
interface FastEthernet0/1
ipv6 enable
ipv6 ospf 1 area 1
!
interface FastEthernet1/0
ipv6 enable
ipv6 ospf 1 area 0
!
ipv6 router ospf 1
router-id 0.0.0.1
log-adjacency-changes
area 1 nssa
!
end
R1# |
R2#<input>show run</input>
hostname R2
!
ipv6 unicast-routing
!
interface Loopback0
ipv6 address 2001::2/128
ipv6 ospf 1 area 0
!
interface FastEthernet0/0
ipv6 enable
ipv6 ospf 1 area 0
!
interface FastEthernet0/1
ipv6 enable
ipv6 ospf 1 area 2
!
interface FastEthernet1/0
ipv6 enable
ipv6 ospf 1 area 0
!
ipv6 router ospf 1
router-id 0.0.0.2
log-adjacency-changes
area 2 nssa
!
end
R2# |
R3 & R4
| R3 | R4 |
|---|---|
R3#<input>show run</input>
hostname R3
!
ipv6 unicast-routing
!
interface Loopback0
ipv6 address 2001::3/128
ipv6 ospf 1 area 1
!
interface FastEthernet0/0
ipv6 enable
ipv6 ospf 1 area 1
!
ipv6 route ::/0 Loopback0
ipv6 router ospf 1
router-id 0.0.0.3
log-adjacency-changes
area 1 nssa default-information-originate metric-type 1
!
end
R3# |
R4#<input>show run</input>
hostname R4
!
ipv6 unicast-routing
!
interface Loopback0
ipv6 address 2001::4/128
ipv6 ospf 1 area 2
!
interface FastEthernet0/0
ipv6 enable
ipv6 ospf 1 area 2
!
ipv6 route ::/0 Loopback0
ipv6 router ospf 1
router-id 0.0.0.4
log-adjacency-changes
area 2 nssa default-information-originate metric-type 1
!
end
R4# |
R5
Why is R5 using R1 as the next-hop for the default gateway? When they should be equal cost. If the areas are normal areas(not NSSA) it works fine...???
R5#<input>show run</input>
hostname R5
!
ipv6 unicast-routing
!
interface Loopback0
no ip address
ipv6 address 2001::5/128
ipv6 ospf 1 area 0
!
interface FastEthernet0/0
ipv6 enable
ipv6 ospf 1 area 0
!
interface FastEthernet0/1
ipv6 enable
ipv6 ospf 1 area 0
!
ipv6 router ospf 1
router-id 0.0.0.5
log-adjacency-changes
!
end
R5#<input>show ipv6 route</input>
IPv6 Routing Table - 8 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
<notice>OE1 ::/0 [110/2]
via FE80::C800:4FF:FE10:1C, FastEthernet0/0</notice>
O 2001::1/128 [110/1]
via FE80::C800:4FF:FE10:1C, FastEthernet0/0
O 2001::2/128 [110/1]
via FE80::C801:4FF:FE10:1C, FastEthernet0/1
OI 2001::3/128 [110/2]
via FE80::C800:4FF:FE10:1C, FastEthernet0/0
OI 2001::4/128 [110/2]
via FE80::C801:4FF:FE10:1C, FastEthernet0/1
LC 2001::5/128 [0/0]
via ::, Loopback0
L FE80::/10 [0/0]
via ::, Null0
L FF00::/8 [0/0]
via ::, Null0
R5#<input>show ipv6 ospf database</input>
OSPFv3 Router with ID (0.0.0.5) (Process ID 1)
Router Link States (Area 0)
ADV Router Age Seq# Fragment ID Link count Bits
0.0.0.1 1785 0x8000000D 0 2 EB
0.0.0.2 1775 0x8000000E 0 2 EB
0.0.0.5 1784 0x8000000D 0 2 None
Net Link States (Area 0)
ADV Router Age Seq# Link ID Rtr count
0.0.0.1 1785 0x80000001 4 2
0.0.0.5 658 0x80000004 4 2
0.0.0.5 658 0x80000004 5 2
Inter Area Prefix Link States (Area 0)
ADV Router Age Seq# Prefix
0.0.0.1 1713 0x80000001 2001::3/128
0.0.0.2 1776 0x80000001 2001::4/128
Link (Type-8) Link States (Area 0)
ADV Router Age Seq# Link ID Interface
0.0.0.2 1780 0x80000004 6 Fa0/1
0.0.0.5 658 0x80000004 5 Fa0/1
0.0.0.1 90 0x80000005 6 Fa0/0
0.0.0.5 658 0x80000004 4 Fa0/0
Intra Area Prefix Link States (Area 0)
ADV Router Age Seq# Link ID Ref-lstype Ref-LSID
0.0.0.1 90 0x80000005 0 0x2001 0
0.0.0.2 1780 0x80000004 0 0x2001 0
0.0.0.5 658 0x80000004 0 0x2001 0
Type-5 AS External Link States
ADV Router Age Seq# Prefix
<notice>0.0.0.1 1693 0x80000001 ::/0
0.0.0.2 1775 0x80000001 ::/0</notice>
R5#