JN0-363 Exam Dumps : Service Provider Routing and Switching, Specialist (JNCIS-SP)

Neighbors Stuck in Exstart/Exchange State The problem occurs most frequently when you attempt to run OSPF between a Cisco router and another vendor router. The problem occurs when the maximum transmission unit (MTU) settings for neighboring router interfaces do not match. If the router with the higher MTU sends a packet larger that the MTU set on the neighboring router, the neighbor router ignores the packet. When this problem occurs, the output of the show ip ospf neighbor command displays output similar to what is shown in this figure.

A mismatched Maximum Transmission Unit (MTU) setting on OSPF interfaces can cause routers to get stuck in the ExStart state. OSPF requires that both sides of a link have the same MTU to form a full adjacency.References:

• OSPF Troubleshooting, Juniper Networks Documentation
• MTU and OSPF, Juniper Networks Documentation

To ensure that MPLS traffic-engineered routes are used without affecting IGP routes in the route tables, the mpls-forwarding traffic engineering setting should be used. This setting allows MPLS to influence forwarding without changing the IGP route selection.References:

• MPLS Traffic Engineering, Juniper Networks Documentation
• Traffic Engineering and LSP Optimization, Juniper Networks Documentation

Theshow bgp neighborcommand in Junos OS provides a detailed description of each BGP session, including session state, options configured, and counters for messages sent and received. This is the command you would use to see a detailed list of all established BGP sessions.

References:

• Juniper Networks documentation on BGP: BGP Commands