Configuring the switch
214
OSPF Area Configuration
To display the following form, go to the OSPF Areas Configuration form. Select an area number, or open
the OSPF Areas folder and click
Add OSPF Area.
The following table describes the OSPF Area Configuration controls:
Table 151
OSPF Area Configuration controls
Control Descriptions
Area number (0-2)
Assigns a numeric identifier for the OSPF area.
Area ID
Defines the area ID of the OSPF area number.
Enabled?
Enables or disables the OSPF area.
Area Type
Defines the type of area. For example, when a virtual link has to be established
with the backbone, the area type must be defined as transit.
•
Transit area: allows area summary information to be exchanged between
routing devices. Any area that is not a stub area or NSSA is considered to be
transit area.
•
Stub area: is an area where external routing information is not distributed.
Typically, a stub area is connected to only one other area.
•
NSSA: Not-So-Stubby Area (NSSA) is similar to stub area with additional
capabilities. For example, routes originating from within the NSSA can be
propagated to adjacent transit and backbone areas. External routes from
outside the Autonomous System (AS) can be advertised within the NSSA but
are not distributed into other areas.
Stub Area Metric (1-65535)
Configures a stub area to send a numeric metric value. All routes received via that
stub area carry the configured metric to potentially influencing routing decisions.
Metric value assigns the priority for choosing the switch for default route. Metric
type determines the method for influencing routing decisions for external routes.
SPF Interval (0-255)
Sets time interval between two successive SPF (shortest path first) calculations of the
shortest path tree using the Dijkstra’s algorithm.