---
name: "pppd-radius"
section: "8"
platform: "linux"
package: "ppp"
version: "2.5.4-2"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/pppd-radius"
---

# pppd-radius(8)

RADIUS authentication plugin for pppd(8)

## NAME

radius.so - RADIUS authentication plugin for [**pppd**(8)](/pppd/8.md)

## SYNOPSIS

**pppd** \[ *options* \] plugin radius.so

## DESCRIPTION

The RADIUS plugin for pppd permits pppd to perform PAP, CHAP, MS-CHAP and MS-CHAPv2 authentication against a RADIUS server instead of the usual */etc/ppp/pap-secrets* and */etc/ppp/chap-secrets* files.

The RADIUS plugin is built on a library called **radiusclient** which has its own configuration files (usually in */etc/radiusclient*), consult those files for more information on configuring the RADIUS plugin

## OPTIONS

The RADIUS plugin introduces one additional pppd option:

- **radius-config-file** *filename*

  The file *filename* is taken as the radiusclient configuration file.  If this option is not used, then the plugin uses */etc/radiusclient/radiusclient.conf* as the configuration file.

- **avpair** *attribute=value*

  Adds an Attribute-Value pair to be passed on to the RADIUS server on each request.

- **map-to-ifname**

  Sets Radius NAS-Port attribute to number equal to interface name (Default)

- **map-to-ttyname**

  Sets Radius NAS-Port attribute value via libradiusclient library

## USAGE

To use the plugin, simply supply the **plugin radius.so** option to pppd, and edit */etc/radiusclient/radiusclient.conf* appropriately.  If you use the RADIUS plugin, the normal pppd authentication schemes (login, checking the /etc/ppp/\*-secrets files) are skipped.  The RADIUS server should assign an IP address to the peer using the RADIUS Framed-IP-Address attribute.

## SEE ALSO

[**pppd**(8)](/pppd/8.md) **pppd-radattr**(8)

## AUTHOR

Dianne Skoll \<dianne@skoll.ca\>