Neighbor Stuck in Init STATE

The init state indicates that a router sees Hello packets from the neighbor, but two-way communication has not been established. A Cisco router includes the router IDs of all neighbors in the init (or higher) state in the neighbor field of its Hello packets. Example 3-15 shows sample output of the show ip ospf neighbor command.

Example 3-15 Output from the show ip ospf neighbor Command

router2#show

ip ospf

neighbor

Neighbor ID

Pri

State

Dead Time Address

Interface

10.10.5.1

1

INIT/-

00:00:34 10.10.1.1

Serial0

router2#

For two-way communication to be established with a neighbor, a router must also see its own router ID in the neighbor field of the neighbor's Hello packets. In other words, a router with a neighbor in the init state has received Hello packets from the neighbor but has not seen its own router ID in the neighbor's Hellos.

The most likely reason a local router is not listed in a neighbor's Hello packets is that the neighbor has not received Hello packets from the local router. Possible reasons for this are as follows:

• If any access lists are defined on the neighbor's interface, the destination IP of 224.0.0.5 must be permitted in the input access list. Remember that OSPF Hello packets have a destination address of 224.0.0.5 (the all OSPF routers multicast address).

A Layer 2 or configuration problem might be keeping multicast packets from reaching the neighboring router. You can test this by pinging the multicast address 224.0.0.5 and confirming that responses are received from the neighboring router(s). In nonbroadcast media, such as frame relay, X.25, and ISDN, mapping is required between Layer 2 and the IP address. For example, in the case of static mapping, in the interface level command frame-relay map ip 1.1.1.1 100 broadcast or dialer map ip 1.1.1.1 broadcast name router1 55346, you must configure the keyword broadcast to avoid encapsulation failure every time OSPF tries to send the multicast Hello packet. The debug ip packet detail command used with the access list shows any encapsulation failures.

OSPF authentication is not enabled on both sides or the passwords do not match. The router on which authentication is not enabled still processes Hello packets from the neighbor and sees the neighbor in the init state. To correct this problem, enable authentication on both sides.

If you are running Cisco IOS Software Release 11.1.9 or earlier, check the output of the show ip ospf interface command for discrepancies such as the following: Neighbor Count is 0, Adjacent neighbor count is 1

If the OSPF adjacent neighbor count is higher than the neighbor count, the neighbor list might be corrupted. This problem has the Cisco bug ID CSCdj01682. If you are a registered CCO user and you have logged in, you can view the bug details.

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