Technical data

BLADE OS 5.1 Application Guide
156
 Chapter 11: OSPF BMD00136, November 2009
Router ID
Routing devices in OSPF areas are identified by a router ID. The router ID is expressed in IP
address format. The IP address of the router ID is not required to be included in any IP interface
range or in any OSPF area, and may even use the G8000 loopback interface.
The router ID can be configured in one of the following two ways:
 Dynamically—OSPF protocol configures the lowest IP interface IP address as the router ID
(loopback interface has priority over the IP interface). This is the default.
 Statically—Use the following command to manually configure the router ID:
If there is a loopback interface, its IP address is always preferred as the router ID, instead of an
IP interface address. The ip router-id command is the preferred method to set the router
ID and it is always used in preference to the other methods.
 To modify the router ID from static to dynamic, set the router ID to 0.0.0.0, save the configura-
tion, and reboot the G8000.
 To view the router ID, use the following command:
Authentication
OSPF protocol exchanges can be authenticated so that only trusted routing devices can participate.
This ensures less processing on routing devices that are not listening to OSPF packets.
OSPF allows packet authentication and uses IP multicast when sending and receiving packets.
Routers participate in routing domains based on pre-defined passwords. BLADE OS supports
simple password (type 1 plain text passwords) and MD5 cryptographic authentication. This type of
authentication allows a password to be configured per area.
Figure 25 shows authentication configured for area 0 with the password test. Simple authentication
is also configured for the virtual link between area 2 and area 0. Area 1 is not configured for OSPF
authentication.
>> # ip router-id <IP address>
>> # show ip ospf