Configuring OSPF

Modify SPF Timers

The routing switch uses the following timers when calculating the shortest path for OSPF routes:

•SPF delay - When the routing switch receives a topology change, the software waits before it starts a Shortest Path First (SPF) calculation. By default, the software waits five seconds. You can configure the SPF delay to a value from 0 – 65535 seconds. If you set the SPF delay to 0 seconds, the software immediately begins the SPF calculation after receiving a topology change.

•SPF hold time - The routing switch waits for a specific amount of time between consecutive SPF calculations. By default, the routing switch waits ten seconds. You can configure the SPF hold time to a value from 0 – 65535 seconds. If you set the SPF hold time to 0 seconds, the software does not wait between consecutive SPF calculations.

You can set the delay and hold time to lower values to cause the routing switch to change to alternate paths more quickly in the event of a route failure. Note that lower values require more CPU processing time.

You can change one or both of the timers. To do so, use the following CLI method.

USING THE CLI

To change the SPF delay and hold time, enter commands such as the following:

HP9300(config-ospf-router)# timers spf 10 20

The command in this example changes the SPF delay to 10 seconds and changes the SPF hold time to 20 seconds.

Syntax: timers spf <delay> <hold-time>

The <delay> parameter specifies the SPF delay.

The <hold-time> parameter specifies the SPF hold time.

To set the timers back to their default values, enter a command such as the following:

HP9300(config-ospf-router)# no timers spf 10 20

USING THE WEB MANAGEMENT INTERFACE

You cannot configure the SPF timers using the Web management interface.

Modify Redistribution Metric Type

The redistribution metric type is used by default for all routes imported into OSPF unless you specify different metrics for individual routes using redistribution filters. Type 2 specifies a big metric (three bytes). Type 1 specifies a small metric (two bytes). The default value is type 2.

USING THE CLI

To modify the default value to type 1, enter the following command:

HP9300(config-ospf-router)# metric-type type1

Syntax: metric-type type1 type2

The default is type2.

USING THE WEB MANAGEMENT INTERFACE

To modify the default metric type:

1.Log on to the device using a valid user name and password for read-write access. The System configuration panel is displayed.

2.Click on the plus sign next to Configure in the tree view to expand the list of configuration options.

3.Click on the plus sign next to OSPF in the tree view to expand the list of OSPF option links.

4.Click on the General link to display the OSPF configuration panel.

5.Select either Type 1 or Type 2 for the redistribution metric type.

8 - 33