OSPF-show ip protocols /Routing Information Resources/Gateway

[MikeNY85]

Hello Professionals,

I was doing some testing for OSPF with packet tracer for a topology of 4 routers. R1,R2,R3,R4. When I issued the command "show ip protocol", the output of the command showed the results shown in the attached photo. As you can see in the routing information resources, the gateways are (1.1.1.1 which is the R1 router ID), 10.1.1.1, 10.1.2.1 and 10.1.2.2. Are these readings legit?...Is it normal to see the router ID listed in the Gateways part?... Any guidance or help would be so much appreciated. Thanks in advance!

[Martin L]

yes, OSPF uses Router ID to indicate your neighboring OSPF router.  Maybe you confusion comes from work of "gateway" which in that particular output means your next door neighbor. 

Also, notice same IP will be used in show ip ospf neigbor

Regards, ML
**Please Rate All Helpful Responses **

[MikeNY85]

@Martin L I think the confusion came because I issued the "show ip protocol" command from R1, and the router ID issued in the Routing Information Resources part (Gateway) was 1.1.1.1 is also for R1. Thanks Martin L!

[MikeNY85]

I think the confusion came because I issued the "show ip protocol" command from R1, and the router ID issued in the Routing Information Resources part (Gateway) was 1.1.1.1 is also for R1.

[Martin L]

oh, right, that Gateway info "1.1.1.1" should not be there in R1 output if and when R1 has 1.1.1.1 IP or router ID.

Nice catch !

Regards, ML
**Please Rate All Helpful Responses **

[MHM Cisco World]

please share the config of all four routers 

[MHM Cisco World]

I will check this issue, update soon 

[MikeNY85]

@MHM Cisco World here are the configurations for all 4 routers.. notice that the loopback add which is going to be the router ID for R1 was also showing on the "show ip protocol" from R1. I just want to confirm that this could be a glitch with packet tracer.

Thanks very much in advance!

R1

R1(config)# int f0/1
R1(config-interface)# ip add 10.0.1.1 255.255.255.0
R1(config-interface)# no shut
R1(config-interface)# exit
R1(config)# int f0/0
R1(config-interface)# ip add 10.0.2.1 255.255.255.0
R1(config-interface)# no shut
R1(config-interface)# exit
R1(config)# int loopb 0
R1(config-interface)# ip add 1.1.1.1 255.255.255.255
R1(config)# router ospf 1
R1(config-router)# network 10.0.0.0 0.255.255.255 area 0

R2

R2(config)# int f0/0
R2(config-interface)# ip add 10.0.2.2 255.255.255.0
R2(config-interface)# no shut
R2(config-interface)# exit
R2(config)# int f0/1
R2(config-interface)# ip add 10.1.2.1 255.255.255.0
R2(config-interface)# no shut
R2(config-interface)# exit
R2(config)# router ospf 1
R2(config-router)# network 10.0.0.0 0.255.255.255 area 0

R3

R3(config)# int f0/1
R3(config-interface)# ip add 10.1.2.2 255.255.255.0
R3(config-interface)# no shut
R3(config-interface)# exit
R3(config)# int f0/0
R3(config-interface)# ip add 10.1.1.2 255.255.255.0
R3(config-interface)# no shut
R3(config-interface)# exit
R3(config)# router ospf 1
R3(config-router)# network 10.0.0.0 0.255.255.255 area 0

R4

R4(config)# int f0/1
R4(config-interface)# ip add 10.0.1.2 255.255.255.0
R4(config-interface)# no shut
R4(config-interface)# exit
R4(config)# int f0/0
R4(config-interface)# ip add 10.1.1.1 255.255.255.0
R4(config-interface)# no shut
R4(config-interface)# exit
R4(config)# router ospf 1
R4(config-router)# network 10.0.0.0 0.255.255.255 area 0

[MHM Cisco World · Accepted solution]

I run lab and I see correct value, so I think it is bug in packet tracer. 

[David Ruess]

Hello,

Looks to be a bug. Could you save your work and restart all devices to see if that clears the issue?

-David

[Martin L · Accepted solution]

PT is just software simulator to mimic behavior of real IOS but it is not real IOS.  There are IOS features missing or not behave exactly the same way as real one does. Some things are simplified and others do not work as they should;  however, PT is still good tool to use when learning networking at CCNA

Routing for Networks: - is what u advertise under that protocol

Routing Information Sources: lists your neighbors running the same protocol that give and exchange routes. Gateway means neighbor and should not listed itself in that section. 

Regards, ML
**Please Rate All Helpful Responses **