No relevant resource is found in the selected language.

This site uses cookies. By continuing to browse the site you are agreeing to our use of cookies. Read our privacy policy>Search

Reminder

To have a better experience, please upgrade your IE browser.

upgrade
Knowledge Base

OSPF Neighbor Is Stuck in 2-Way State and Cannot Be Established on the AR2831

Publication Date:  2012-07-27  |   Views:  517  |   Downloads:  0  |   Author:  Du Lizhi  |   Document ID:  EKB0000352425

Contents

Issue Description

Network topology:
AR2831(ETH0)---ospf --(ETH0)AR2831
The OSPF neighbor on the AR2831 is stuck in 2-way state.
<R2>disp ospf peer                                                              
                                                                                
                 OSPF Process 1 with Router ID 2.2.2.2                          
                                Neighbors                                       
                                                                                
  Area 0.0.0.0 interface 192.168.1.240(Ethernet0/0)'s neighbor(s)               
  RouterID: 192.168.1.254   Address: 192.168.1.254                              
        State: 2 Way  Mode: None    Priority: 0                                 
        DR: None  BDR: None                                                     
        Dead timer expires in 34s                                               
        Neighbor has been up for 00:00:00 
<R1>disp ospf peer                                                              
                                                                                
                 OSPF Process 1 with Router ID 192.168.1.254                    
                                Neighbors                                       
                                                                                
  Area 0.0.0.0 interface 192.168.1.254(Ethernet0/0)'s neighbor(s)               
  RouterID: 2.2.2.2         Address: 192.168.1.240                              
        State: 2 Way  Mode: None    Priority: 0                                 
        DR: None  BDR: None                                                     
        Dead timer expires in 35s                                               
        Neighbor has been up for 00:00:00

Alarm Information

Null

Handling Process

If only the two routers in this network establish the OSPF neighbor relationship, they cannot enter the 2-way state.
Check the configurations. All the interfaces used to send OSPF information are configured with the ospf dr-priority 0 command.
interface Ethernet0/0                                                           
 ip address 192.168.1.254 255.255.255.0                                         
 ospf dr-priority 0
If you configure the ospf dr-priority 0 command on a router, the router will not participate the DR/BDR election.
The default priority is 1. The router that has the highest priority in the network wins the DR election. If all the routers use the default priority, the router with the largest router ID wins the DR election.
If all the routers on an Ethernet network segment are configured with priority 0, then no router on this network segment will enter the Full state.
Therefore, you must ensure that the priority of at least one router on a network segment is not 0.
To solve the problem, run the undo ospf dr-priority 0 command. Then the OSPF neighbor relationship can be established.

Root Cause

1. Networking problem
2. Configuration problem

Suggestions

Null