3Com 10014299 manual Configuring a Peer for the Nbma Interface, Cost

428CHAPTER 29: CONFIGURING OSPF

Configure sending packet cost	ospf	cost	cost
Reset the sending packet cost	undo	ospf	cost

The default value of the cost of sending a packet on the interface is calculated automatically according to the interface baud rate as follows:

The default value is automatically calculated according to interface baud rate.

■If the baud rate is less than 2000 bps, 2000 is taken, and the overhead value is 100000000/2000=50000.

■If the baud rate is greater than 100000000 bps, 100000000 is taken, and the overhead value is 100000000/100000000=1.

■If the baud rate is between 2000 bps and 100000000bps, the overhead value is the result of 100000000/interface rate.

Configuring a Peer for Special configuration is needed for the network of an NBMP interface. Since the the NBMA Interface adjacent router cannot be found by broadcasting hello packets, the IP address of

the adjacent router should be specified manually for the interface, as well as whether the adjacent router has a voting right. This is specified with the ospf peer ip-address[eligible] command. To use the eligible attribute, this adjacent router must have no voting right.

On X.25 and frame relay networks, you can configure a map to make the whole network fully connected so there is a virtual circuit between any two routers ont eh network and they are directly reachable. Then OSPF can process like a broadcast network. The IP address of the adjacent router, and whether it has a voting right, must be specified manually for the interface because the adjacent router cannot be found dynamically by broadcasting hello packets.

Perform the following configurations in interface view.

Table 492 Configuring a Peer for the NBMA Interface

Operation	Command
Configure a peer for NBMA interface	ospf	peer ip-address[eligible]
Cancel or delete a peer for NBMA interface	undo	ospf peer ip-address

By default, no peer of the NBMA interface is specified.

When you configure the peer of the NBMA interface, the following items are necessary:

■The configured hello timer and dead timer between neighbors must be identical.

■The configured link route type betwen neighbors must be identical.

■The area number that neighbors belong to must be identical.

■The authentication mode (simple text or MD5), authentication password, and key-id of the area that neighbors belong to must be identical.

■The configured stub attribute of the areas including the neighbors must be consistent.