topic Re: ASA OSPF routes in Network Security

ASA OSPF routes

Ganesh Iyyappan Pillai — Fri, 21 Feb 2020 09:28:40 GMT

Below is my setup,

on the router R2

interface Loopback0

ip address 150.1.2.2 255.255.255.0

interface Loopback1

ip address 192.168.1.2 255.255.255.0

interface Loopback2

ip address 192.168.3.2 255.255.255.0

interface Loopback3

ip address 192.168.5.2 255.255.255.0

interface Ethernet0/0

ip address 136.1.0.2 255.255.255.0

router ospf 1

router-id 150.1.2.2

log-adjacency-changes

network 136.1.0.0 0.0.0.255 area 0

network 150.1.2.0 0.0.0.255 area 0

network 192.168.1.0 0.0.0.255 area 0

network 192.168.3.0 0.0.0.255 area 0

network 192.168.5.0 0.0.0.255 area 0

routes on the asa,

C 136.1.0.0 255.255.255.0 is directly connected, outside

O 192.168.5.2 255.255.255.255 [110/11] via 136.1.0.2, 0:14:11, outside

O 192.168.1.2 255.255.255.255 [110/11] via 136.1.0.2, 0:14:11, outside

O 150.1.2.2 255.255.255.255 [110/11] via 136.1.0.2, 0:14:11, outside

O 192.168.3.2 255.255.255.255 [110/11] via 136.1.0.2, 0:14:11, outside

on the ASA, I see the host routes instead of the networks, Am I missing something? Thanks in advance

Ganesh

Re: ASA OSPF routes

Jon Marshall — Tue, 10 Apr 2007 13:33:25 GMT

Hi Ganesh

It's not a problem with the ASA but to do with how OSPF advertises loopback addresses. By default OSPF advertises loopback addresses as /32's regardless of the subnet mask you actually use. If you want to to advertise the subnet mask as well you need to add the following to your config

interface loopback0

ip address 150.1.2.2 255.255.255.0

ip ospf network point-to-point

Do this under all your loopback interfaces.

HTH

Jon

Re: ASA OSPF routes

Ganesh Iyyappan Pillai — Tue, 10 Apr 2007 13:36:41 GMT

yes, you are right. it worked 🙂

Thanks Jon

Re: ASA OSPF routes

Jon Marshall — Tue, 10 Apr 2007 13:44:45 GMT

No problem. Glad to have helped.