The main process is called fdpi_radius. It is installed as a service in the system and managed using standard service commands.
Restart the service:

systemctl fastradius restart

FastRADIUS settings are located in the /etc/dpi directory:

• fdpi_radius.conf — configuration file
• prefixes.info — region settings (prefixes for subscriber logins), file is absent if not needed

Parameters in the configuration file are either "hot" or "cold":

• Hot parameters can be changed during operation "on the fly," i.e., without restarting the service.
• Cold parameters will only take effect after restarting the service.

Update hot settings without restarting the service:

systemctl fastradius reload

FastRADIUS logs are located in the /var/log/dpi directory:

• fdr_alert.log — log for informational messages and errors
• fdr_stat.log — log for statistical information

Log rotation is handled by the standard logrotate tool; by default, logs are stored for 24 hours.

The logrotate configuration file: /etc/logrotate.d/fdpi_radius
If the administrator changes the retention period, they must ensure sufficient disk space remains available.

Depending on the settings, FastRADIUS may write the following information to the /var/dump/dpi directory:

• spdu_*.pcap - pcap files containing records of bad or all RADIUS packets
• uip_*.txt - text logs with information about IP address allocation and release

In this case, it is necessary to implement manual cleanup to prevent disk overflow.

Configured in the fdpi_radius.conf file

syslog_level— the level at which messages from the alert log are written to syslog.

Possible values:

• 0 — syslog logging is disabled (default value)
• 7 — syslog logging is enabled (7 is the level up to which messages are logged in syslog)