User Manual

Routing
265
M6100 Web Management User Guide
 Configure the OSPF Configuration settings.
7. In the Router ID field, enter the 32-bit integer in dotted decimal format that uniquely
identifies the router within the autonomous system (AS). If you want to change the
Router ID, you must first disable OSPF. After you set the new Router ID, you must
reenable OSPF to have the change take effect. The default value is 0.0.0.0, although
this is not a valid Router ID.
8. In the Admin Mode field, select Enable or Disable from the list. If you select Enable, OSPF
will be activated for the switch. The default value is Enable. You must configure a Router ID
before OSPF can become operational. You do this on the IP Configuration page, or by
issuing the CLI command: config router id. For more information, see
IP Configuration on
page 217.
9. In the RFC 1583 Compatibility field, select Enable or Disable from the list to specify the
preference rules that will be used when choosing among multiple AS-external-LSAs
advertising the same destination. If you select Enable, the preference rules will be those
defined in Section 16.4.1 of the OSPF-2 standard (RFC 2328), which prevents routing loops
when AS-external-LSAs for the same destination have been originated from different areas.
The default value is Enable. All routers in the OSPF domain must be configured the same.
If all OSPF routers are capable of operating according to RFC 2328, RFC 1583
Compatibility should be disabled.
10. Set the Opaque LSA Status to Enable if OSPF should store and flood opaque LSAs. An
opaque LSA is used for flooding user-defined information within an OSPF router domain.
11. When the number of non-default external LSAs exceeds a configured limit, the router enters
an overflow state as defined in RFC 1765. Use the Exit Overflow Interval field to specify
how long in seconds OSPF must wait before attempting to leave overflow state. In overflow
state, OSPF cannot originate non-default external LSAs. If the Exit Overflow Interval is 0,
OSPF will not leave overflow state until it is disabled and reenabled. The range is 0 to
2,147,483,647 seconds. The default is 0.
12. Configure the SPF Delay Time - the number of seconds from when OSPF receives a
topology change to the start of the next SPF calculation. Delay Time is an integer from 0 to
65535 seconds. The default is 5 seconds. A value of 0 means that there is no delay; that is,
the SPF calculation is started upon a topology change.
13. Configure the SPF Hold Time - the minimum time in seconds between two consecutive
SPF calculations. The range is 0 to 65,535 seconds. The default time is 10 seconds. A
value of 0 means that there is no delay; that is, two SPF calculations can be done, one
immediately after the other.
14. Use the External LSDB Limit field to set the number of the external LSDB limit for OSPF. If
the value is –1, then there is no limit. When the number of non-default AS-external-LSAs in
a router’s link-state database reaches the external LSDB limit, the router enters overflow
state. The router never holds more than the external LSDB limit none-default
AS-external-LSAs in the database. The external LSDB limit must be set identically in all
routers attached to the OSPF backbone and/or any regular OSPF area. The range for the
External LSDB Limit field is –1 to 2147483647. The default value is –1.
15. Use the Default Metric field to set a default for the metric of redistributed routes. This field
is blank if a default metric has not been configured. The range of valid values is 1 to
16777214. The default value is 0.
16. Use the Maximum Paths field to set the number of paths that OSPF can report for a given
destination. The range of valid values is 1 to 16. The default value is 4.