Cisco Certified Expert

Field

Explanation

FastEthernet1/0 is up, line protocol

This should be seen as two statements. The first half of the

is up

sentence indicates that the physical line is operational. This

meaning differs with the type of interface; for Ethernet, it

indicates the presence of the transceiver. The second portion

of the sentence indicates that the data link layer is working.

Internet Address 140.100.17.129/28,

The IP address and mask configured on the interface.

Area 3

Area 3

The OSPF area for which the interface is configured.

Process ID 100, Router ID

The autonomous system number, which is in fact the OSPF

140.100.32.10

process ID.

The router ID that will be advertised in the LSA updates.

Network Type BROADCAST

The type of network that the interface is connected to, which

indicates how neighbors are found and adjacencies are

formed.

Cost: 1

The metric cost of the link, which, although not stated, was

probably dynamically chosen using the Cisco defaults.

Transmit Delay is 1 sec

The anticipated time taken to send an update to the neighbor.

The default is 1 second.

State DR

The state of the link in reference to establishing adjacencies.

This field is extremely useful in troubleshooting. Here are the

states in order:

DOWN—Heard from no one.

ATTEMPT—Sent a hello on an NBMA, but haven't heard

Field

Explanation

Priority 100

The priority is sent in the Hello protocol and is used to

determine the election of the designated router and the

backup designated router. The value of 1 means that the

router is prepared to be elected. If every other router has the

priority of 1, the highest router ID will select the routers.

Designated Router (ID)

The address of the elected designated router. Note that the ID

140.100.32.10, Interface address

and the interface ID differ. This is a useful field for

140.100.17.129

troubleshooting misconfiguration.

Backup Designated router (ID)

The address of the backup designated router. Note that both

140.100.23.1, Interface address

the ID and the interface are given, and they differ.

140.100.17.130

Timer intervals configured, Hello 10,

It is possible to change these timers and sometimes necessary

Dead 40, Wait 40, Retransmit 5

if connecting to another vendor's equipment that has

different defaults. These timers should be consistent

throughout the area. The defaults are as follows:

Hello: 10

Dead: 40

Wait: 40

Retransmit: 5

Hello due in 00:00:06

When the next hello packet is due to be sent out of the

interface.

Neighbor Count is 3, Adjacent

The number of routers that have neighbor relationships.

neighbor count is 2

Note that the number of routers with which adjacency is

established is less than the number of neighbors. This is

because there is a designated router and a backup designated

router, whose responsibility it is to maintain the adjacencies

with all routers on the LAN.