My problem is that if I add over 3 access points to my WLAN network DNS stops working on Android devices. All other operating systems are working (Windows 7, Windows 10, iPhones).
I've looked on properties of Android device and it gets IP and DNS normally. Sometimes on WLAN properties there's an error Connected, no internet and Connected, but Chrome browser always gives an error dns_probe_finished_nxdomain. I've tried other browsers also.
The access points are configured to bridge all traffic and there's PfSense virtual machine which acts as a DHCP server. User authentication is handled by FreeRADIUS 3 on an Ubuntu 16.04 virtual machine. I've tried to configure PfSense to use DNS Resolver and DNS Forwarder without any success.
My network:
All the access points are TP-Link Archer C7 v2 wireless running with OpenWRT Chaos Calmer and with same configuration. I've checked that it's not one particular AP that messes the network, but always if I connect over 3 APs, Androids start to fail.
On OpenWRT I've disabled DHCP and firewall.
uci set dhcp.lan.ignore=1
uci commit dhcp
/etc/init.d/dnsmasq restart
/etc/init.d/firewall disable
/etc/init.d/firewall stop
Here's OpenWRT's network configuration /etc/config/network:
config interface 'loopback'
option ifname 'lo'
option proto 'static'
option ipaddr '127.0.0.1'
option netmask '255.0.0.0'
config globals 'globals'
option ula_prefix 'fd7f:9df2:3177::/48'
config interface 'lan'
option ifname 'eth0 eth1'
option force_link '1'
option type 'bridge'
option proto 'static'
option netmask '255.255.0.0'
option ip6assign '60'
option ipaddr '192.168.33.20'
config switch
option name 'switch0'
option reset '1'
option enable_vlan '1'
config switch_vlan
option device 'switch0'
option vlan '1'
option ports '0 2 3 4 5'
config switch_vlan
option device 'switch0'
option vlan '2'
option ports '1 6'
And here's OpenWRT's wireless configuration /etc/config/wireless:
config wifi-device 'radio0'
option type 'mac80211'
option hwmode '11a'
option path 'pci0000:01/0000:01:00.0'
option htmode 'VHT80'
option txpower '17'
option channel '48'
option disabled '0'
config wifi-iface
option device 'radio0'
option network 'lan'
option mode 'ap'
option ssid 'mywlan'
option auth_server '192.168.33.1'
option auth_port '1812'
option auth_secret 'XXX'
option encryption 'wpa2'
config wifi-device 'radio1'
option type 'mac80211'
option channel '3'
option hwmode '11g'
option path 'platform/qca955x_wmac'
option htmode 'HT20'
option txpower '23'
option disabled '0'
config wifi-iface
option device 'radio1'
option network 'lan'
option mode 'ap'
option ssid 'mywlan'
option auth_server '192.168.33.1'
option auth_port '1812'
option auth_secret 'XXX'
option encryption 'wpa2'