Configuration reload not working

[Jouni Malinen]

On Thu, Oct 19, 2017 at 10:27:01AM +0200, Léo Serre wrote:
> I'm trying to change the configuration dynamically (without reboot).
> I'm running hostapd v2.6 built using Buildroot on my device.
> 
> Hostapd is started from the `/etc/network/interfaces` using that rule:
> `post-up /usr/sbin/hostapd -B /etc/hostapd.conf -P /var/run/hostapd.pid`
> 
> Once started, I just change the ssid in the configuration file, and launched
> `kill -s SIGHUP 270` where 270 is my PID number.
> I waited more than 5 minutes without viewing any changes on the SSID.

SIGHUP to change SSID works for me, but maybe there are some drivers
that do not allow that type of changes to be performed without fully
disabling and re-enabling the BSS. You could try to enabling debugging
to a file in hostapd ("-d -f /tmp/hostapd.log" added to the command line
and CONFIG_DEBUG_FILE=y in hostapd/.config build configuration) to see
what is happening when the SIGHUP is received.

That said, the most robust way of changing configuration would be over
the control interface and with full DISABLE/ENABLE cycle around the
operations:

hostapd_cli DISABLE
hostapd_cli SET ssid new-ssid
hostapd_cli ENABLE

-- 
Jouni Malinen                                            PGP id EFC895FA