



= Radutmp Module

The `radutmp` module writes a `utmp` style file, of which users are
currently logged in, and where they've logged in from.

This file is used mainly for `Simultaneous-Use` checking,
and also `radwho`, to see who's currently logged in.

See also `man 5 utmp`.



## Configuration Settings


filename:: Where the file is stored.

It's not a log file, so it doesn't need rotating.



username:: The field in the packet to key on for the users name.

If you have other fields which you want to use to key on to control
`Simultaneous-Use`, then you can use them here.

However, that the size of the field in the `utmp` data
structure is small, around `32` characters, so that will limit
the possible choices of keys.

TIP: You may want instead: `%{&Stripped-User-Name || &User-Name}`.



check_with_nas:: Accounting information may be lost, so the user MAY
have logged off of the NAS, but we haven't noticed.

If so, we can verify this information with the NAS.

If we want to believe the 'utmp' file, then this configuration entry
can be set to `no`.



permissions:: Set the file permissions, as the contents of this file
are usually private.



caller_id:: If enabled, it will extract the field `link:https://freeradius.org/rfc/rfc2865.html#Calling-Station-Id[Calling-Station-Id]` from
the packet and store as `username` information.

Default is `no`.


== Default Configuration

```
radutmp {
	filename = ${logdir}/radutmp
	username = %{User-Name}
	check_with_nas = yes
	permissions = 0600
#	caller_id = "yes"
}
```
