OSPF help CIsco Packet Tracer

[bmahar904]

Hello, I am trying to ping between all of the computers, but I can't figure out what I am doing wrong.  Can someone help me please.  I am using OSPF.  Thank you. 

[Mark Malone]

If you load up the config files Ill take a look for you , most engineers on this forum wont be using PK to be able to load that file to see it

[bmahar904]

Thank you for your response.  I have uploaded the confs for each router in the zip folder.  Thank you

[Mark Malone]

Hi

 its hard to tell without screenshot of topology if you could take 1

But I do see 1 major issue just looking at the configs there all area 1 , you must use an OSPF area 0 its a prerequisite for OSPF to work correctly

I would take a guess thats exactly your problem without seeing topology

https://supportforums.cisco.com/discussion/11246526/why-area-0-backbone-area-ospfneed-complete-answer

RFC

In OSPF domains the area topology is restricted so that there must be a backbone area (area 0) and all other areas must have either physical or virtual connections to the backbone. The reason for this star-like topology is that OSPF inter-area routing uses the distance-vector approach and a strict area hierarchy permits avoidance of the "counting to infinity" problem. OSPF prevents inter-area routing loops by implementing a split-horizon mechanism, allowing ABRs to inject into the backbone only Summary-LSAs derived from the intra-area routes, and limiting ABRs' SPF calculation to consider only Summary-LSAs in the backbone area's link-state database.

[bmahar904]

That is kind of strange, I usually use area 1 for all of them and they work fine.  I have never used area 0.  Also I will attach my network as an image.  You sure it HAS to be area 0?  Seems strange to me.  Thank you very much for your message and response.  

[Mark Malone]

I know it seems a bit strange but in real world you will never have a network without area 0 , its the backbone, just have a quick google you will see , its just one of those things saying that it should not stops pings or connectivity if just 1 area in use completely but its bad practice to run ospf without area 0

Do you have neighbor relationships between the routers can you ping between them ok ? , i see you have class C subnets on the ints but then Class B advertised in the process is there a reason for this

[bmahar904]

Yes, i can ping between them just fine.  Thank you

[Mark Malone]

Ok thats good OSPF is working then something else is up if your neighbour relationships have formed and you can ping as example from router 2-5 without issue. That shows the IGP is working so each router should see each others network in its show ip route

The switches is there any config on them even default-gateway or are they non managed(un-configured) ?

Are the pcs set with the correct subnet mask and default gateway closest ip interface  ,  can they ping there default gateway ok, when you run a trace from a pc to pc where does it stop at the switch or router or further ?

Best to try an isolate the issue between 2 close routers/pcs first like 2 and 3 once you fix that its prob same issue for the rest of the setup

[bmahar904]

Oh wait I am sorry.  I am unable to ping from router 2 to router 5.  I just checked.  I was doing the wrong routers.  

[Mark Malone]

sorry only getting back now was very late last night , can you as a test just change say router 1/2 and 3 the ospf process and make them class C and make sure your PCs have same correct gateway and subnet to match as that’s whats being advertised on the interfaces , just for ease of troubleshooting I would make them the same as the interfaces that you have set

Something else I see between like router 2 and r1 the actual subnets match but the ip range does not one side is 198.7.247 but there is no 198.1.247 on the R1 interface config these need to match to form OSPF neighbour , change the R1 interface to match R2 to .247 , subnets like class B can overlap class C but the ip ranges must match between your interfaces that needs to be fixed for it to work R2 S0/2 – R1 R S0/2 , R3 to R1 looks to be the same .244 - .246 these need to match

example

2

router ospf 1

log-adjacency-changes

network 198.7.247.0 0.255.255.255 area 1

network 10.1.1.0 0.255.255.255 area 1

3

router ospf 1

log-adjacency-changes

network 198.7.247.0 0.255.255.255 area 1

network 10.1.1.0 0.255.255.255 area 1

1 No requirement for 10 network to be advertised in router 1 as it doesn’t have a local network there

router ospf 1

log-adjacency-changes

network 198.7.247.0 0.255.255.255 area 1

network 198.7.246.0 0.255.255.255 area 1

Then please post the show ip route & show ip ospf neigh from each of the routers 1/2/3 and we will see whats happening

[bmahar904]

I believe i did what you asked me to do.  Here they are.  Thank you for helping me, i appreciate it. 

[bmahar904]

By the way I was able to get it to work.  Thank you so much for all of the help!

[Borgenstrand]

Great that you got it to work!

Please rate and please move the question from unanswered to answered by selecting the right answer. Thanks.

[Borgenstrand]

Hi, I downloaded the packet tracer file and I found two issues. It seems like Router0 want to use authentication towards Router1 but Router1 is not aware of that. After removing ip ospf authentication on serial0/1 on Router0, the neighborship between Router0 and Router1 came up.

After that it was only one network missing. That was 10.1.2.0/24 network. It seems like Router3 is using the wrong network command for its WAN interface. 

These were the commands I did:

Router0:
configure terminal
interface s0/1
no ip ospf authentication

Router3:
configure terminal
router ospf 1
no network 198.7.0.0 0.0.0.255 area 1
network 198.7.246.0 0.0.0.255 area 1