Switch 7700 Configuration Guide

80 CHAPTER 5: ROUTING PROTOCOL OPERATION
Perform the following configuration in OSPF Area view.
You must specify the segment to which the OSPF will be applied after enabling the
OSPF tasks.
Configure Router ID
A router ID is a 32-bit unsigned integer that uniquely identifies a router within an
AS. A router ID can be configured manually. If a router ID is not configured, the
system selects the IP address of an interface automatically. When you set a router
ID manually, you must guarantee that the IDs of any two routers in the AS are
unique. A common undertaking is to make the router ID the same as the IP
address of an interface on the router.
Perform the following configurations in system view.
To ensure the stability of OSPF, the you must determine the division of router IDs
and manually configure them when implementing network planning.
Configure the Network Type on the OSPF Interface
The route calculation of OSPF is based on the topology of the adjacent network of
the local router. Each router describes the topology of its adjacent network and
transmits it to all the other routers.
OSPF divides networks into four types by link layer protocol:
■ Broadcast: If Ethernet or FDDI is adopted, OSFP defaults the network type to
broadcast.
■ Non-Broadcast Muli-access (NBMA): If Frame Relay, ATM, HDLC or X.25 is
adopted, OSPF defaults the network type to NBMA.
■ Point-to-Multipoint (P2MP): OSPF does not default the network type of any link
layer protocol to P2MP. The general undertaking is to change a partially
connected NBMA network to P2MP network if the NBMA network is not
fully-meshed.
■ Point-to-point (P2P): If PPP, LAPB or POS is adopted, OSPF defaults the network
type to P2P.
As you configure the network type, consider the following points:
■ NBMA means that a network is non-broadcast and multi-accessible. ATM is a
typical example. You can configure the polling interval to specify the interval of
Tab le 23 Specify Interface
Operation Command
Specify an interface to run OSPF network ip-address ip-mask
Disable OSPF on the interface undo network ip-address ip-mask
Tab le 24 Configure Router ID
Operation Command
Configure router ID router id router-id
Remove the router ID undo router id