OSPF

You can manage OSPF routes from Sophos Firewall. Add, update, or delete the areas, networks, and interface-specific configuration.

Open Shortest Path First (OSPF) is a link-state routing protocol that multicasts the routing information to all the hosts within a single network. It sends routing information to all the routers in the network by calculating the shortest path to each router based on the structure built up by each router.

OSPF areas

An area is a logical division of an OSPF network. Each area maintains a separate database on the connecting router which contains information about the area's topology. The topology of an area isn't known outside of that area. There are three types of areas, as shown in the table below:

Area name

Description

Backbone area

The backbone area, also known as area 0, distributes information between the other areas in the network. All other areas in the network are connected to the backbone. Routing between areas takes place using routers connected to the backbone and the other areas.

Stub area

A stub area is an area that does not receive route advertisements external to the autonomous system (AS) (a collection of networks under a common network operator that share the same routing policy).

NSSA

A not-so-stubby-area (NSSA) is a type of stub area that can import AS external routes in a limited amount.

An Area Border Router (ABR) is a router that connects areas to the backbone network and maintains separate routing information for each area to which it's connected. It has interfaces in more than one area, with at least one interface in the backbone area.

Global configuration

Setting

Description

Router ID

Router ID is a basic setting. All other settings listed in the table are advanced settings.

Specify a unique router ID. Example: 12.34.5.66.

Default metric

Specify the default metric value used for redistributed routes.

Metric is a property that contains a value used by a routing protocol to decide whether traffic must take a specific route or not.

Default: 1

Acceptable range: 1 to 16777214

ABR type

Select the type of Area Border Router (ABR).

The available options are standard, Cisco, IBM, and shortcut.

Auto cost reference bandwidth (Mbits/s)

Specify the cost reference to calculate the OSPF interface cost based on bandwidth.

Default: 100 Mbits/s

Acceptable range: 1 to 4294967

Default information originate

Select an option to control the distribution of the default route.

The available options are Never (default setting), Regular, and Always.

If you select Regular or Always, you must provide the metric and select the metric type.

Redistribute connected

Click to turn on the redistribution of connected routes into the OSPF routing table.

Specify the metric and the metric type for redistributing connected routes.

Acceptable range: 0 to 16777214

Metric type: External type 1 or External type 2

Redistribute static

Click to turn on the redistribution of static routes into the OSPF routing table.

Specify the metric and the metric type for redistributing static routes.

Acceptable range: 0 to 16777214

Metric type: External type 1 or External type 2

Redistribute RIP

Click to turn on the redistribution of OSPF routes into the OSPF routing table.

Specify the metric and the metric type for redistributing RIP routes.

Acceptable range: 0 to 16777214

Metric type: External type 1 or External type 2

Redistribute BGP

Click to turn on the redistribution of BGP routes into the OSPF routing table.

Specify the metric and the metric type for redistributing BGP routes.

Acceptable range: 0 to 16777214

Metric type: External type 1 or External type 2

Networks & areas

Under Networks & areas, the Networks section lists all available OSPF networks, the corresponding netmasks, and the area to which they belong. You can add a new OSPF network here. The Areas section lists all available OSPF areas, specifies their types and authentication type, the area cost, and, if available, virtual links. For more information, see Add OSPF areas and Add OSPF network.

Override interface configuration

You can manage the interface configuration here. For more information, see Override interface configuration.