Let’s move on to OSPF authentication.
First, basic clear text authentication.
OSPFv2 supports three types of authentication:
Type 0= null authentication (no authentication)
Type 1= clear text authentication
Type 2= MD5 authentication or HMAC-SHA authentication.
Configure OSPF clear text authentication between R6 and R7.
Configuration and verification:
There is two way to configure clear text authentication.
First way, at the process level but we still have to configure the password at the interface level:
R6(config)#router ospf 10 R6(config-router)#area 10 authentication R6(config-router)#int Eth 0/2 R6(config-if)#ip ospf authentication-key CISCO
Second way, at the interface level:
R7(config)#int Eth 0/0 R7(config-if)#ip ospf authentication R7(config-if)#ip ospf authentication-key CISCO
To verify that authentication is correctly configure we can use the following:
R6#sh ip ospf Routing Process "ospf 10" with ID 126.96.36.199 Start time: 00:00:26.660, Time elapsed: 01:47:57.451 SNIP Area 10 Number of interfaces in this area is 1 Area has simple password authentication
On R7, because authentication is not set at the process level, we don’t see it when using the “show ip ospf” command:
R7#sh ip ospf Routing Process "ospf 10" with ID 188.8.131.52 Start time: 00:00:26.764, Time elapsed: 01:48:37.673 SNIP Area 10 Number of interfaces in this area is 4 (1 loopback) Area has no authentication
We need to verify that with the following command:
R7#sh ip ospf int Eth 0/0 Ethernet0/0 is up, line protocol is up Internet Address 10.10.67.2/30, Area 10, Attached via Interface Enable Process ID 10, Router ID 184.108.40.206, Network Type POINT_TO_POINT, Cost: 10 SNIP Neighbor Count is 1, Adjacent neighbor count is 1 Adjacent with neighbor 220.127.116.11 Suppress hello for 0 neighbor(s) Simple password authentication enabled
Neighbor adjacency is UP so it is working fine:
R7#sh ip ospf neigh Neighbor ID Pri State Dead Time Address Interface 18.104.22.168 0 FULL/ - 00:00:34 10.10.67.1 Ethernet0/0
Let’s now see the type 2 authentication.
Thank you for reading.
OSPF – Implement and troubleshoot authentication – Clear text authentication