I have a Raspberry Pi 3 with an external WiFi antenna wlan1 set up as an independent IoT access point without Internet connection following this tutorial, using hostap and isc-dhcp server. I omitted the Network Access Translation part. The AP worked well up to the point when I tried connecting wlan0 to my router at home for accessing the Internet via the GUI.
/etc/network/interfaces looks like this
auto lo iface lo inet loopback iface eth0 inet manual allow-hotplug wlan0 iface wlan0 inet manual wpa-conf /etc/wpa/supplicant/wpa_supplicant.conf allow-hotplug wlan1 iface wlan1 inet static address 192.168.42.1 netmask 255.255.255.0
I setup the daemon
sudo service hostapd start sudo service isc-dhcp-server start
sudo update-rc.d hostapd enable sudo update-rc.d isc-dhcp-server enable
and this all worked before I started messing with wlan0.... But now on boot when hovering over the GUI it says "wlan1: Disassociated from Pi3AP" and
sudo service hostapd status prints
Loaded: loaded (/etc/init.d/hostapd) Active: active (exited) since ... 31 mins ago Process: 571 ExecStart=/etc/init.d/hostapd start (code=exited, status=0/SUCCESS)
sudo service isc-dhcp-server status
returns an error
raspberrypi dhcpd: receive_packet failed on wlan1: Network is down
When I run
sudo /usr/sbin/hostapd /etc/hostapd/hostapd.conf
all works again but nothing on reboot. Can someone spot at where the error lies? Somehow the network GUI and/or the two wlan interfaces seem to be interfering with each other.