The establishment of OSPF limit FULL Neighbor Relationship in Multiple Access Networks

OSPF limits the establishment of the FULL Neighbor Relationship-practice 2

Uses OSPF port authentication to establish the adjacent relationship.

The OSPF port on R1 is configured as follows:

 
 

  
  
Interface FastEthernet1/0
  
  
Ip address 1.1.123.1 255.255.255.0
  
  
Ip ospf authentication message-digest start authentication
  
  
Ip ospf message-digest-key 1 md5 cisco specifies the key required for authentication
 
 

The OSPF port on R2 is configured as follows:

 
 

  
  
Interface FastEthernet1/0
  
  
Ip address 1.1.123.2 255.255.255.0
  
  
Ip ospf authentication message-digest start authentication
  
  
Ip ospf message-digest-key 2 md5 ccxx specifies the key required for authentication
 
 

The OSPF port on R3 is configured as follows:

 
 

  
  
Interface FastEthernet1/0
  
  
Ip address 1.1.123.3 255.255.255.0
  
  
Ip ospf authentication message-digest start authentication
  
  
Ip ospf message-digest-key 1 md5 cisco specifies the key required for authentication
  
  
Ip ospf message-digest-key 2 md5 ccxx specifies the key required for authentication
 
 

OSPF limits the establishment of FULL Neighbor Relationship-method 3

It is adjusted through the DR election mechanism of OSPF. The OSPF priority of ports R1 and R2 running OSPF can be adjusted to 0, so that the two drothers between R1 and R2 form a 2-way relationship, but do not form a FULL relationship, in this way, the LSA is not exchanged between R1 and R2.

 
 

  
  
R1# show ip ospf neighbor  
  
  
Neighbor ID     Pri   State           Dead Time   Address         Interface  
  
  
1.1.123.2         0   2WAY/DROTHER    00:00:30    1.1.123.2       FastEthernet1/0  
  
  
1.1.123.3         1   FULL/DR         00:00:32    1.1.123.3       FastEthernet1/0  
  
  
 
  
  
R2# show ip ospf neighbor  
  
  
Neighbor ID     Pri   State           Dead Time   Address         Interface  
  
  
1.1.123.1         0   2WAY/DROTHER    00:00:37    1.1.123.1       FastEthernet1/0  
  
  
1.1.123.3         1   FULL/DR         00:00:35    1.1.123.3       FastEthernet1/0  
  
  
 
  
  
R3# show ip ospf neighbor  
  
  
Neighbor ID     Pri   State           Dead Time   Address         Interface  
  
  
1.1.123.1         0   FULL/DROTHER    00:00:33    1.1.123.1       FastEthernet1/0  
  
  
1.1.123.2         0   FULL/DROTHER    00:00:39    1.1.123.2       FastEthernet1/0 
 
 

The establishment of OSPF's limit on the FULL neighbor relationship has been completed. I hope you can learn it through practice. For more information, see setting up OSPF to limit the FULL relationship.