(4)OSPF的hello组播地址被ACL Block

R1#
interface Ethernet0
ip address 131.108.1.1 255.255.255.0
ip access-group 100 in
!
access-list 100 permit tcp any any
access-list 100 permit udp any any
access-list 101 permit ip 131.108.1.0 0.0.0.255 host 224.0.0.5


R2#
interface Ethernet0
ip address 131.108.1.2 255.255.255.0
ip access-group 100 in
!
access-list 100 permit tcp any any
access-list 100 permit udp any any
access-list 101 permit ip 131.108.1.0 0.0.0.255 host 224.0.0.5


R2#debug ip packet 101 detail
IP packet debugging is on (detailed) for access list 101
IP: s=131.108.1.2 (Ethernet0), d=224.0.0.5, len 68, access denied, proto=89

这时候的邻居关系是INIT

R2#show ip ospf neighbor
Neighbor ID   Pri  State    Dead Time   Address         Interface
131.108.2.1    1  INIT/-   00:00:33    131.108.1.1     Ethernet0

R1#show access-list 101
Extended IP access list 101
    permit ip 131.108.1.0 0.0.0.3 host 224.0.0.5 (8 matches)
R1#debug ip packet 101 detail
IP packet debugging is on (detailed) for access list 101
R1#
IP: s=131.108.1.1 (local), d=224.0.0.5 (Ethernet0), len 60, sending broad/multicast,
proto
=89
IP: s=131.108.1.2 (Ethernet0), d=224.0.0.5, len 82, access denied, proto=89
IP: s=131.108.1.1 (local), d=224.0.0.5 (Ethernet0), len 60, sending broad/multicast,
proto
=89

IP: s=131.108.1.2 (Ethernet0), d=224.0.0.5, len 82,access denied, proto=89


(5)在broadcast链路上的子网掩码不匹配

(6)Hello/dead 间隔不匹配
(7)认证方式或者是认证密码不匹配

  使用debug ip ospf adj 来查看,可以自己使用不同的情况来验证

转载地址：http://www.net130.com/CMS/Pub/Tech/tech_instance/2006_02_13_90412_2.htm