Step
2.
Enter OSPF view.
3.
Enter area view.
4.
Configure a virtual link.
Configuring OSPF network types
OSPF classifies networks into the following types based on the link layer protocol:
Broadcast—When the link layer protocol is Ethernet or FDDI, OSPF classifies the network type as
•
broadcast by default.
NBMA—When the link layer protocol is Frame Relay, ATM, or X.25, OSPF classifies the network
•
type as NBMA by default.
P2P—When the link layer protocol is PPP, LAPB, or HDLC, OSPF classifies the network type as P2P
•
by default.
When you change the network type of an interface, follow these guidelines:
•
When an NBMA network becomes fully meshed, change the network type to broadcast to avoid
manual configuration of neighbors.
If any routers in a broadcast network do not support multicasting, change the network type to
•
NBMA.
An NBMA network must be fully meshed. OSPF requires that an NBMA network be fully meshed.
•
If a network is partially meshed, change the network type to P2MP.
If a router on an NBMA network has only one neighbor, you can change the network type to P2P
•
to save costs.
Two broadcast-, NBMA-, and P2MP-interfaces can establish a neighbor relationship only when they are
on the same network segment.
Configuration prerequisites
Before you configure OSPF network types, complete the following tasks:
Configure IP addresses for interfaces to ensure IP connectivity between neighboring nodes.
•
•
Enable OSPF.
Command
ospf [ process-id | router-id
router-id | vpn-instance
vpn-instance-name ] *
area area-id
vlink-peer router-id [ dead seconds
| hello seconds | { { hmac-md5 |
md5 } key-id { cipher cipher-string
| plain plain-string } | simple
{ cipher cipher-string | plain
plain-string } } | retransmit
seconds | trans-delay seconds ] *
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Remarks
N/A
N/A
By default, no virtual link is
configured.
Configure this command on both
ends of a virtual link, and the hello
and dead intervals must be identical
on both ends of the virtual link.