---
name: "rlm_unix"
section: "5"
platform: "linux"
package: "freeradius"
version: "3.2.10-4"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/rlm_unix"
---

# rlm\_unix(5)

FreeRADIUS Module

## NAME

rlm\_unix - FreeRADIUS Module

## DESCRIPTION

The *rlm\_unix* module reads [crypt(3)](/crypt/3.md) passwords from the system password file, and allows the server to use them for authentication. The module also provides FreeRADIUS an interface into a radwtmp file (used by "radlast") when added to the accounting section.

The *rlm\_unix* module should be listed in the "authenticate" section.  Please see the default *radiusd.conf* shipped with the server for an example of the correct usage of this module.

As of FreeRADIUS 1.1.0, the module no longer reads, or caches /etc/passwd, /etc/shadow, or /etc/group.  If you wish to cache those files, see *rlm\_passwd*.  Most, if not all, configurations should not need those files to be cached.

The main configuration items to be aware of are:

- radwtmp

  The path to the system wtmp file to be used for keeping the database of online users as read by the 'radlast' program.

## CONFIGURATION

```

modules {
  ...
  unix {
    radwtmp = ${logdir}/radwtmp
  }
  ...
}
```

## SECTIONS

**authentication,** **accounting**

## FILES

*/etc/raddb/radiusd.conf,*

## SEE ALSO

[**radiusd**(8)](/radiusd/8.md), [**radiusd.conf**(5)](/radiusd.conf/5.md), [**rlm\_passwd**(5)](/rlm_passwd/5.md), [**radlast**(1)](/radlast/1.md)

## AUTHORS

Chris Parker, cparker@segv.org