neighbor command in router ospf command

[kishorecisco]

hi i would like to know whether a neighbor command can be added into a router ospf configuration mode.

[mrdogantr]

#conf t

config#router ospf 100

(config-router)#network 2.2.2.1 0.0.0.0 area 0

(config-router)#end

#wr

hth

Muammer

[Talha Ansari]

Yes you can give neighbor command in router ospf configuration mode. By doing this the OSPF will send its updates as unicast rather than multicast.

[andre.ortega]

Yes,

This is used for nonbroadcast networks usually.

Ex:

conf t

router ospf 100

neighbor ip-address [cost]

See http://www.cisco.com/en/US/docs/ios/12_0/np1/configuration/guide/1cospf.html#wp4801

Regards.

[madhu.kumar_2]

OSPF classifies different media into the following three types of networks by default:

•Broadcast networks (Ethernet, Token Ring, FDDI)

OSPF messages sent on broadcast networks use IP multicast addresses.

•Point-to-point networks (HDLC, PPP)

OSPF messages sent on point-to-point networks use IP multicast addresses.

•Nonbroadcast multiaccess networks (SMDS, Frame Relay, X.25)

A network that can connect more than two routers but has no hardware broadcast facility. X.25,

Frame Relay, and ATM are Non-Broadcast Multiple Access (NBMA) networks. Because multicasted OSPF messages do not reach all the OSPF routers on the network, OSPF must be configured to unicast to the IP addresses of the routers on the NBMA network.

Static neighbours can be defined in all the types , but it has to be defined in NBMA reason is OSPF multicast msg are not recognised or not reached the neighbour on NBMA (Point-to-multipoint is different case it can go through Multicast)

in the configuration i see that the ospf is not applied to interface , you must do that to form neighbour adjacency

let me know if this explanation helped you

[cadet alain]

Static neighbours can be defined in all the types , but it has to be defined in NBMA 

Not if you change default ospf network type.

[kishorecisco]

Thanks to All