Updated: April 19, 2023

Daemon for access point and authentication servers


hostapd-version [-BdhKtv] [-e entropy_file] [-f output_file] [-G group]
    [-g global_ctrl_interface] [-i interface_names] [-P PID_file] [-Z num] 
    config-file1 [config-file2...]

Runs on:

QNX Neutrino


Detach from the controlling terminal and run as a daemon process in the background.
Note: Use of this option is not recommended. The preferred method for starting hostapd in daemon mode is to append & to the command line.
Enable debugging messages. If this option is supplied twice (-dd), more verbose messages are displayed.
-e entropy_file
Specify the (readable and writable) entropy file for the hostapd utility to use.
-f output_file
Send the output to the specified file, instead of to standard output.
-G group
The name of the global_ctrl_interface group.
-g global_ctrl_interface
The path to the global_ctrl_interface socket.
Show help text.
-i interface_names
A comma-separated list of the names of the wireless interfaces to use.
Include key information in debugging output.
Note: This option is meant for debugging only. Don't use it in a production setting.
-P PID_file
Specify the location of the PID file.
Include timestamps in some debugging output.
Display version information, then exit.
-Z num
(QNX Neutrino extension; QNX Neutrino 7.0 or later) Specify the number of 4 KB pages for the slog2 buffer. The minimum is 5, the default is 10, and the maximum is 500.
config-file1 [config-file2...]
The full paths to one or more configuration files.

These configuration files can be used to define AP options. The distribution package contains a sample configuration file. This is installed as /usr/share/examples/hostapd/hostapd.conf for you to use as a basis for configuration. It includes examples of all supported configuration options and a short description of each option. Start the hostapd utility with a full path to at least one configuration file as a command-line argument; for example, /etc/hostapd.conf. The files contain the names of the wireless interfaces to use.


The hostapd utility is a user-space daemon for access point and authentication servers. It implements IEEE 802.11 access point management, IEEE 802.1X/WPA/WPA2/EAP Authenticators, RADIUS client, EAP server, and RADIUS authentication server. The current version supports Linux (Host AP, madwifi, mac80211-based drivers) and FreeBSD (net80211).

The utility runs in the background and acts as the backend component for controlling authentication. It supports separate frontend programs, including a text-based frontend, hostapd_cli, which is included with hostapd.

The number in the hostapd utility name indicates the WPA version it supports. For example, hostapd-2.9 supports version 2.9.

To use hostapd as an authenticator, the underlying device must support some basic functionality, such as the ability to set security information in the 802.11 management frames. Note that not all devices have this support.

To reload changes to the configuration file, send a SIGHUP signal to the hostapd processor, or use the hostapd_cli reconfigure command.

This program uses the OpenSSL library for cryptography services.

Supported WPA/IEEE 802.11i/EAP/IEEE 802.1X features

Supported EAP methods (integrated EAP server and RADIUS authentication server)

The following methods are also supported but because they don't generate keying material, they can't be used with WPA or IEEE 802.1X WEP keying:
  • EAP-MD5-Challenge
  • EAP-TNC (Trusted Network Connect; TNCS, IF-IMV, IF-T, IF-TNCCS)