HOSTAPD(8)                  System Manager's Manual                 HOSTAPD(8)


     hostapd - Host Access Point daemon


     hostapd [-dv] [-D macro=value] [-f file]


     hostapd is a daemon which allows communication between different 802.11
     wireless access points running in Host AP mode.

     hostapd implements the Inter Access Point Protocol (IAPP).  Its purpose
     is to exchange station association updates between access points in large
     wireless networks.  IAPP has been designed to speed up roaming between
     different access points in the same Extended Service Set (ESS).  IAPP is
     described in the IEEE 802.11f standard.

     hostapd additionally allows the monitoring and logging of station
     associations on a non-hostap host which is receiving IAPP messages.

     hostapd uses two network interfaces on startup specified in the
     configuration file hostapd.conf(5).  The first interface is used to
     access the Host AP, which is a wireless interface running in Host AP
     mode.  Host AP mode can be enabled using ifconfig(8).  The second
     interface is used to communicate with other hostapd in the same broadcast
     domain or multicast group.  Usually a wired interface is used to
     communicate with other hostapd.

     hostapd broadcasts an ADD.notify IAPP message when a new station is
     associated to the Host AP.  When hostapd receives an ADD.notify message
     it tells the Host AP to remove the specified station.

     hostapd may also handle dynamic roaming of IP addresses and routes in
     addition to the standard IAPP ADD.notify behaviour.  See the section
     called IP Roaming in hostapd.conf(5) for details.

     The options are as follows:

     -D macro=value
             Define macro to be set to value on the command line.  Overrides
             the definition of macro in the configuration file.

     -d      Do not daemonize and log to stderr.

     -f file
             Use file as the configuration file, instead of the default

     -v      Produce more verbose output.


     /etc/hostapd.conf     default hostapd configuration file


     hostapd.conf(5), ifconfig(8)

     Inter Access Point Protocol, IEEE 802.11f, March 2001.


     The hostapd program first appeared at the 21st Chaos Communication
     Congress ( and later in OpenBSD 3.8.


     The hostapd program was written by Reyk Floeter <>.


     hostapd depends on drivers using the net80211 kernel wireless layer with
     support of Host AP mode.  For traditional reasons, the wi(4) driver still
     uses its own Host AP code in if_wi_hostap(), which is not supported by

     The IEEE 802.11 WLAN protocol lacks authentication of management frames
     and is vulnerable to various denial of service and man-in-the-middle
     attacks.  That should be considered when implementing wireless networks
     with hostapd.

OpenBSD 6.4                     March 26, 2015                     OpenBSD 6.4

[Unix Hosting | Open-Source | Contact Us]
[Engineering & Automation | Software Development | Server Applications]