#ospf #tshoot #ospf tshoot #ospf tshoot #ospf tshoot
***OSPF Neighbor List is Empty
1. is ospf enabled on the interface ?
2. is the interface in between up/up?
3. is the interface defined as passive?
4. is the access list blocking ospf hellos?
5. is this a broadcast media segment?
6. do the hello and dead interfals match on both sides
7. does the authentication type match on both sides?
8. does the authentication type match on both sides?
9. are both sides configured with the correct authentication key?
10. are both sides configured with matching area IDs?
11. is there any stub/transit/NSSA mismatch?
12. is there router attempting to form an ospf neighbor relationship through a secondary ip address?
13. is ospf running on an asynchronous interface?
14. is ospf running over an NBMA interface?
15. is ospf running over and NBMA interface?
16. is ospf running over a frame relay or a dialer interface?
***OSPF Neighbor stuck in ATTEMPT
1. is the neighbor statement properly configured?
2. is the neighbor reachable through ping?
***OSPF Neighbor Stuck in INIT
1. is the access list blocking ospf hellos on one side?
2. is there a Catalyst 6500 switch between the neighboring routers?
3. is the authentication enabled on only one side?
4. is the keyword broadcast missing from frame-relay map or dialer-map statement?
5. are ospf hellos getting lost at layer2 on one side?
***OSPF Neighbor Stuck in 2-WAY
1. is priority 0 configured on all the routers?
***OSPF Neighbor Stuck in EXSTART/EXCHANGE
1. is there and MTU mismatch between neighbors?
2. is the neighboring router’s ID the same as the local router?
3. is the neighbor reachable through ping with a large MTU size?
4. is the neighbor reachable through ping?
5. is this between pri and bri/dialer interfaces?
***OSPF Neighbor Stuck in Loading
1. is there MTU mismatch?
2. is the link-state request packet corrupted?
***OSPF Neighbor is not advertising routes
1. is ospf enabled on the interface that is supposed to be advertised?
2. is the advertising interface down?
3. is this a secondary network defined under and interface?
***OSPF Neighbor (ABR) Not advertising the summary route
1. is this area configured as a totally stubby area?
2. is the ABR connected to area )?
3. Has area 0 become discontiguous?
***OSPF Neighbor is not advertising external routes
1. is this area defined as a stub area?
2. is this a type 7 LSA that should be translated by the NSSA ABR into a type 5 LSA
***OSPF Neighbor not advertising default routes
1. is the default-information originate command configured properly in the neighbor’s ospf configuration?
2. is the default route present in the neighbor’s routing table?
3. is the neighbor trying to originate a default route into a stub area?
4. is the NSSA ABR/ASBR missing the area default-information originate command?
***OSPF not installing any routes in the routing table
1. is there a network type mismatch across the link?
2. is the ip address flipped across dual link? is the wrong ip subnet/mask applied across the link?
3. is one side numbered and the others side and unnumbered point-to-point link?
4. is distribute-list in blocking route installation?
5. is there a broken frame relay pvc in a fully meshed, ospf broadcast environment?
***OSPF not installing external routes in the routing table
1. is the forwarding address known through ospf interarea or intra-area?
2. is ABR generated type4 summary LSA?
***OSPF neighbor is not advertising external routes
1. is the keyword subnets added to the redistribution command is the ASBR?
2. is distribute-list out blocking the routes from a neighbor?
***Router is not summarizing interarea routes
1. is the area range command configured on the ABR?
***Router is not summarizing external routes
1. is the summary-adress command configured on the ASBR?
***CPUHOG messages during adjacency formation
1. is the router running packet pacing code?
***CPUHOG messages during LSA refresh period
1. is the router running LSA group pacing code?
***OSPF hellos are bringing up the link
1. are ospf hellos included in the interesting traffic definition?
***Demand circuit keeps on bringing up the link
1. is there a link flap in the network?
2. is network type defined as broadcast?
3. is a ppp host route being redistributed into ospf?
4. is there any router in the ospf network running a version of cisoc ios software earlier than release 11.2?
***SPF Running constantly
1. is any link within the network flapping?
2. is there any neighbor within the network flapping?
3. is there a duplicate router ID?