F Commands

This chapter describes the Cisco NX-OS Open Shortest Path First (OSPF) commands that begin with F.

feature ospf

To enable the Open Shortest Path First Protocol (OSPF), use the feature ospf command. To disable OSPF, use the no form of this command.

feature ospf

no feature ospf

 
Syntax Description

This command has no arguments or keywords.

 
Command Default

Disabled

 
Command Modes

Global configuration mode

 
Command History

Release
Modification

5.2(1)N1(1)

This command was introduced.

 
Usage Guidelines

You must enable the OSPF feature before you can configure OSPF.

Note In Cisco NX-OS Release 5.2(1)N1(1), a software upgrade on the Cisco Nexus 5548 switch and the Cisco Nexus 5596 switch that has the Layer 3 features enabled is disruptive. You must reload the switch and the Cisco Nexus 2000 Series Fabric Extender.

This command requires the LAN Base Services license.

Examples

This example shows how to enable the OSPF feature:

switch# configure terminal
switch(config)# feature ospf
switch(config)#
 

This example shows how to disable the OSPF feature:

switch# configure terminal
switch(config)# no feature ospf
switch(config)#

 
Related Commands

Command
Description

router ospf

Creates an OSPF instance.

show feature

Displays the status of features on a switch.

show ospf

Displays OSPF configuration information.

flush-routes (OSPF)

To flush routes on a restart for the Open Shortest Path First (OSPF) protocol, use the flush-routes command. To disable this feature, use the no form of this command.

flush-routes

no flush-routes

 
Syntax Description

This command has no arguments or keywords.

 
Command Default

Disabled

 
Command Modes

Router configuration mode

 
Command History

Release
Modification

5.2(1)N1(1)

This command was introduced.

 
Usage Guidelines

This command causes OSPF to unregister from the unicast RIB when OSPF shuts down. The unicast RIB removes all the routes associated with this OSPF instance. If you do not configure the flush-routes command, OSPF does not unregister and the OSPF routes will be stale. The OSPF routes are eventually removed from the unicast RIB after a timeout period.

This command requires the LAN Base Services license.

Examples

This example shows how to flush routes for an OSPF restart:

switch# configure terminal
switch(config)# router ospf 202
switch(config-router)# flush-routes
switch(config-router)#

 
Related Commands

Command
Description

show ip ospf

Displays OSPF information.