Hi misc,
I've been playing with OSPF on OpenBSD and Cisco and there's something
I can't get my head around. I hope someone is able to point my in the
right direction.
Let me first explain the setup; output of the devices follows at the end.
I have a setup of two Cisco routers (IOS 12.4.25g) and one OpenBSD
router (5.3 i386). All routers have an interface connected to area 0.
The interfaces are defined as follows:
router1: fa0/0, 10.0.0.1/24
router2: fa0/0, 10.0.0.2/24
soekris: sis1, 10.0.0.3/24
Each router also have a loopback interface:
router1: lo1, 1.1.1.1
router2: lo1, 2.2.2.2
soekris: lo1, 3.3.3.3
On the "other" side of the routers I have defined a dedicated areafor
each router:
router1: area 0.0.0.1
router2: area 0.0.0.2
soekris: area 0.0.0.3
In the dedicated area I've added the following interface:
router1: vlan101, 10.101.0.1/24
router2: vlan102, 10.102.0.1/24
soekris: sis2, 10.103.0.1/24
When I start ospfd, all routers are able to see each other. On soekris
I'm also able to see the networks from the areas behind router1 and
router2:
----
soekris:~# ospfctl sh nei
ID Pri State DeadTime Address Iface Uptime
1.1.1.1 1 FULL/BCKUP 00:00:00 10.0.0.1 sis0 00:21:48
2.2.2.2 1 FULL/DR 00:00:00 10.0.0.2 sis0 00:21:43
----
soekris:~# ospfctl sh fib ospf
flags: * = valid, O = OSPF, C = Connected, S = Static
Flags Prio Destination Nexthop
*O 32 1.1.1.1/32 10.0.0.1
*O 32 2.2.2.2/32 10.0.0.2
*O 32 10.0.0.0/24 10.0.0.3
*O 32 10.101.0.0/24 10.0.0.1
*O 32 10.102.0.0/24 10.0.0.2
----
However on the Cisco routers I'm not able to see the dedicated network
behind soekris:
----
router1#sh ip route ospf
2.0.0.0/32 is subnetted, 1 subnets
O 2.2.2.2 [110/2] via 10.0.0.2, 00:21:48, FastEthernet0/0
3.0.0.0/32 is subnetted, 1 subnets
O 3.3.3.3 [110/11] via 10.0.0.3, 00:21:48, FastEthernet0/0
10.0.0.0/24 is subnetted, 3 subnets
O IA 10.102.0.0 [110/2] via 10.0.0.2, 00:21:48, FastEthernet0/0
----
When I add a secondary OpenBSD router (eeepc) behind soekris in area
0.0.0.3 (as a stub router) the networks in area 0.0.0.3 are shown on
the Cisco routers (eeepc has 4.4.4.4 as loopback interface):
----
router1#sh ip route ospf
2.0.0.0/32 is subnetted, 1 subnets
O 2.2.2.2 [110/2] via 10.0.0.2, 00:00:16, FastEthernet0/0
3.0.0.0/32 is subnetted, 1 subnets
O 3.3.3.3 [110/11] via 10.0.0.3, 00:00:16, FastEthernet0/0
4.0.0.0/32 is subnetted, 1 subnets
O IA 4.4.4.4 [110/21] via 10.0.0.3, 00:00:06, FastEthernet0/0
10.0.0.0/24 is subnetted, 4 subnets
O IA 10.102.0.0 [110/2] via 10.0.0.2, 00:00:16, FastEthernet0/0
O IA 10.103.0.0 [110/11] via 10.0.0.3, 00:00:16, FastEthernet0/0
----
I've seen on the Cisco routers the following that might point to the
cause of the issue(?) When eeepc is not active the Cisco router shows
soekris as "ASBR":
----
router1#sh ip ospf border-routers
OSPF Process 1 internal Routing Table
Codes: i - Intra-area route, I - Inter-area route
i 2.2.2.2 [1] via 10.0.0.2, FastEthernet0/0, ABR, Area 0, SPF 37
i 3.3.3.3 [1] via 10.0.0.3, FastEthernet0/0, ASBR, Area 0, SPF 37
----
When eeepc is active the Cisco shows soekris as "ASR/ASBR" and routes
from area 0.0.0.3 are available on the Cisco routers:
----
router1#sh ip ospf border-routers
OSPF Process 1 internal Routing Table
Codes: i - Intra-area route, I - Inter-area route
i 2.2.2.2 [1] via 10.0.0.2, FastEthernet0/0, ABR, Area 0, SPF 36
i 3.3.3.3 [1] via 10.0.0.3, FastEthernet0/0, ABR/ASBR, Area 0, SPF 36
----
So, now my question is: how can I get soekris to be seen as an ABR
without using eeepc? Is it because the Cisco routers see soekris as an
ASBR that they don't add 10.103.0.0/24 and 4.4.4.4/32 to their routing
table? I also played with the rfc1583 compatibility mode but without
luck.
Anybody have a clue how to solve this? Please let me know if you need
any other output.
Thanks in advance,
Stijn
Here's the output of the ospf config and interfaces.
router1:
----
router ospf 1
router-id 1.1.1.1
no compatible rfc1583
log-adjacency-changes
passive-interface Vlan101
network 1.1.1.1 0.0.0.0 area 0
network 10.0.0.0 0.0.0.255 area 0
network 10.101.0.0 0.0.0.255 area 1
interface FastEthernet0/0
ip address 10.0.0.1 255.255.255.0
ip ospf authentication message-digest
ip ospf message-digest-key 1 md5 7 130A04020D5C
ip ospf dead-interval minimal hello-multiplier 5
duplex auto
speed auto
end
----
router2:
----
router ospf 1
router-id 2.2.2.2
no compatible rfc1583
log-adjacency-changes
passive-interface Vlan102
network 2.2.2.2 0.0.0.0 area 0
network 10.0.0.0 0.0.0.255 area 0
network 10.1.0.0 0.0.0.255 area 0
network 10.102.0.0 0.0.0.255 area 2
interface FastEthernet0/0
ip address 10.0.0.2 255.255.255.0
ip ospf authentication message-digest
ip ospf message-digest-key 1 md5 7 0504151F271C
ip ospf dead-interval minimal hello-multiplier 5
duplex auto
speed auto
end
----
soekris:
----
soekris:~# ifconfig sis0
sis0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1500
lladdr 00:00:24:c5:ef:9c
priority: 0
media: Ethernet autoselect (100baseTX full-duplex)
status: active
inet 10.0.0.3 netmask 0xffffff00 broadcast 10.0.0.255
inet6 fe80::200:24ff:fec5:ef9c%sis0 prefixlen 64 scopeid 0x1
----
soekris:~# cat /etc/ospfd.conf
# $OpenBSD: ospfd.conf,v 1.4 2007/06/19 16:49:56 reyk Exp $
# macros
# global configuration
router-id 3.3.3.3
redistribute connected
fast-hello-interval msec 200
router-dead-time minimal
router-priority 3
rfc1583compat no
# areas
area 0.0.0.0 {
interface sis0 {
auth-type crypt
auth-md 1 "ospf0"
auth-md-keyid 1
}
interface sis1 {
auth-type crypt
auth-md 1 "ospf1"
auth-md-keyid 1
}
interface lo1 {
passive
}
}
area 0.0.0.3 {
# stub redistribute default
interface sis2 {
auth-type crypt
auth-md 1 "ospf2"
auth-md-keyid 1
}
}
----
eeepc:
----
eeepc:~# cat /etc/ospfd.conf
# global configuration
router-id 4.4.4.4
fast-hello-interval msec 200
router-dead-time minimal
router-priority 0
rfc1583compat no
# areas
area 0.0.0.3 {
# stub
interface lii0 {
auth-type crypt
auth-md 1 "ospf2"
auth-md-keyid 1
}
interface lo1 {
passive
}
}
FYI, eeepc is started as a stub router automatically because IP
forwarding is not enabled.
