OSPFD.CONF(5) | File Formats Manual | OSPFD.CONF(5)

# NAME

`ospfd.conf` — OSPF routing daemon configuration file

# DESCRIPTION

The ospfd(8) daemon implements the Open Shortest Path First protocol version 2 as described in RFC 2328.

The `ospfd.conf` config file is divided into the following main sections:

Macros
  Definitions of variables that can be used later, simplifying the configuration file.
Global configuration
  Global settings for ospfd(8). A number of global settings can be overruled in specific areas or interfaces.
Areas
  An OSPF router must be a member of at least one area. Areas are used to group interfaces, simplifying configuration.

Argument names not beginning with a letter, digit, or underscore must be quoted.

Additional configuration files can be included with the `include` keyword, for example:

    include "/etc/ospfd.sub.conf"

## Macros

A macro is defined with a command of the form name=value. The macro name can contain letters, digits, and underscores and cannot be a reserved word (for example, `area`, `interface`, or `hello-interval`). Within unquoted arguments, the string $name is later expanded to value.

For example:

    hi="5"
    area 0.0.0.0 {
    	interface em0 {
    		hello-interval $hi
    	}
    }

The same can be accomplished by specifying the hello-interval globally or within the area declaration.

## Global configuration

All interface related settings can be configured globally, per area and per interface. The only settings that can be set globally and not overruled are listed below.

`fib-priority` prio
  Set the routing priority to prio. The default is 32.

`fib-update` (`yes`|`no`)
  If set to `no`, do not update the Forwarding Information Base, a.k.a. the kernel routing table. The default is `yes`. Setting `fib-update` to `no` will implicitly set the `stub router` option to ensure that no traffic tries to transit via this router.

`rdomain` tableid
  Specifies the routing table ospfd(8) should modify. Table 0 is the default table.

[`no`] `redistribute` (`static`|`connected`|`default`) [`set ...`] [`depend on` interface]
[`no`] `redistribute` prefix [`set ...`] [`depend on` interface]
[`no`] `redistribute rtlabel` label [`set ...`] [`depend on` interface]
  If set to `connected`, routes to directly attached networks will be announced over OSPF. If set to `static`, static routes will be announced over OSPF. If set to `default`, a default route pointing to this router will be announced over OSPF. It is possible to specify a network range with prefix; networks need to be part of that range to be redistributed. Additionally it is possible to redistribute based on route labels using the `rtlabel` keyword. By default no additional routes will be announced over OSPF.

  `redistribute` statements are evaluated in sequential order, from first to last. The first matching rule decides if a route should be redistributed or not. Matching rules starting with `no` will force the route to be not announced. The only exception is `default`, which will be set no matter what, and additionally `no` cannot be used together with it.

  With the `depend on` option, redistributed routes will have a metric of 65535 if the specified interface is down or in state backup. This is especially useful on a carp cluster to ensure all traffic goes to the carp master.

  It is possible to set the route `metric` and `type` for each redistribute rule. `type` is either 1 or 2. The default value for `type` is 1 and for `metric` is 100. Setting more than one option needs curly brackets:

      redistribute static set { metric 300 type 2 }

  The use of `redistribute` prefix | rtlabel can result in higher CPU usage, since ospfd(8) will need to process more route updates.

`rfc1583compat` (`yes`|`no`)
  If set to `yes`, decisions regarding AS-external routes are evaluated according to RFC 2328. The default is `no`.

`router-id` address
  Set the router ID; if not specified, the numerically lowest IP address of the router will be used.

`rtlabel` label `external-tag` number
  Map route labels to external route tags and vice versa. The external route tag is a non-negative 32-bit number attached to AS-external OSPF LSAs.

`spf-delay` (seconds|`msec` milliseconds)
  Set the SPF delay. The delay between receiving an update to the link state database and starting the shortest path first calculation. The default value is 1 second; valid range is 10 milliseconds-10 seconds.

`spf-holdtime` (seconds|`msec` milliseconds)
  Set the SPF holdtime. The minimum time between two consecutive shortest path first calculations. The default value is 5 seconds; the valid range is 10 milliseconds-5 seconds.

`stub router` (`yes`|`no`)
  If set to `yes`, all interfaces with active neighbors will have a metric of infinity. This ensures that the other routers prefer routes around this router while still being able to reach directly connected IP prefixes. The `stub router` option is automatically enabled if either the sysctl(8) variable net.inet.ip.forwarding is set to a value other than 1 or if the FIB is not coupled.

## Areas

Areas are used for grouping interfaces. All interface-specific parameters can be configured per area, overruling the global settings. These interface-specific parameters need to be defined before the interfaces.

`area` id | address
  Specify an area section, grouping one or more interfaces.

      area 0.0.0.0 {
      	hello-interval 3
      	interface em0
      	interface em1 {
      		metric 10
      	}
      }

Area specific parameters are listed below.

`demote` group [count]
  Increase the carp(4) demotion counter by count on the given interface group, usually carp, when no neighbor in the area is in an active state. The demotion counter will be decreased when one neighbor in that area is in an active state. The default value for count is 1.

  For more information on interface groups, see the `group` keyword in ifconfig(8).

`stub` [`redistribute default`] [`set ...`]
  Mark the area as stub. Stub areas will not be flooded by as-ext LSA, resulting in smaller routing tables. Area border routers should redistribute a default network LSA; this can be enabled by specifying the default redistribute option. A default summary LSA will only be redistributed if the router has an active connection to the backbone area 0.0.0.0.

## Interfaces

Each interface can have several parameters configured individually, otherwise they are inherited. An interface is specified by its name. If multiple networks are configured, an additional IP address can be supplied. By default the first IP address is used.

    interface em0 {
    	auth-type crypt
    	auth-md 1 "yotVoo_Heypp"
    	auth-md-keyid 1
    }
    interface fxp0:192.168.1.3

Interface-specific parameters are listed below.

`auth-key` key
  Set the authentication key for `simple` authentication. Up to 8 characters can be specified.
`auth-md` key-id key
  Set the authentication key-id and key for `crypt` authentication. The valid range for key-id is 0-255. Up to 16 characters can be specified for key. Multiple keys may be specified.
`auth-md-keyid` key-id
  Configure the key-id to use for `crypt` authentication. The valid range for key-id is 0-255. The default key-id is 1. While key-id 0 is valid, it is unavailable on various other implementations.
`auth-type` (`none`|`simple`|`crypt`)
  Set the authentication type. The default is `none`. Simple authentication uses a plaintext password, up to 8 characters. Crypt authentication uses an MD5 hash.
`demote` group
  Increase the carp(4) demotion counter by 1 on the given interface group, usually carp, when the interface state is going down. The demotion counter will be decreased when the interface state is active again.
`depend on` interface
  A metric of 65535 is used if the specified interface is down or in status backup.
`fast-hello-interval msec` milliseconds
  If the interface is configured to use `router-dead-time minimal`, hello packets will be sent using this timer. The default value is 333; valid range is 50-333 milliseconds.
`hello-interval` seconds
  Set the hello interval. The default value is 10; valid range is 1-65535 seconds.
`metric` cost
  Set the interface metric a.k.a. cost. The default value is 10; valid range is 1-65535. A metric of 65535 is used for carp(4) interfaces with status backup.
`passive`
  Prevent transmission and reception of OSPF packets on this interface. The specified interface will be announced as a stub network. Passive mode is enforced for carp(4) interfaces.
`retransmit-interval` seconds
  Set retransmit interval. The default value is 5 seconds; valid range is 5-3600 seconds.
`router-dead-time` (seconds|`minimal`)
  Set the router dead time, a.k.a. neighbor inactivity timer. The default value is 40 seconds; valid range is 2-2147483647 seconds. If the router dead time has been set to `minimal`, the timer is set to 1 second and hello packets are sent using the interval specified by `fast-hello-interval`. When a neighbor has been inactive for router-dead-time, its state is set to DOWN. Neighbors that have been inactive for more than 24 hours are completely removed.
`router-priority` priority
  Set the router priority. The default value is 1; valid range is 0-255. If set to 0, the router is not eligible as a Designated Router or Backup Designated Router.
`transmit-delay` seconds
  Set the transmit delay. The default value is 1; valid range is 1-3600 seconds.
`type p2p`
  Set the interface type to point to point. This disables the election of a DR and BDR for the given interface.

# FILES

/etc/ospfd.conf
  ospfd(8) configuration file.
/etc/examples/ospfd.conf
  Example configuration file.

# SEE ALSO

ospfctl(8), ospfd(8), rc.conf.local(8)

# HISTORY

The `ospfd.conf` file format first appeared in OpenBSD 3.7.

July 8, 2025 | Debian