mDNS not working with wireless clients (Linksys EA6350v3 19.07)

Installing and Using OpenWrt Network and Wireless Configuration
1

Hi -

I have a wireless router (Linksys EA6350v3 running openwrt 19.07) with a unifi AP (in bridge mode) connected to the LAN port for extending wireless to a different corner of the house.

All my chromecasts are connected over wireless to the router. The router also runs avahi and the chromecasts can be seen on the wired side of the network (actually technically the uplink - but ignore this), wireless clients connecting to the unifi AP can see all the chromecasts. Wireless clients connecting to the router directly cannot see any of the chromecasts.

Previously I had a near identical setup a TPLink C5 Archer in the place of the Linksys and in that case wireless clients connecting to both could see all the chromecasts, since replacing the C5 I experience the problem described above.

I assumed it might be down to the isolate settings - but this should default to zero according to the documentation - and is unset in the GUI, so I'm not sure what else I should check.

2

Can you try something else, like a ping, from one wireless router host to a chromecast to verify the isolation?
Although, isolation would make sense if host and chromecast were connected on same AP.
Post also from 6350 the following: uci show network ; uci show wireless ; uci show firewall

3

Pings from one wireless host to the chromecast(s) work.

uci show network

network.loopback=interface
network.loopback.ifname='lo'
network.loopback.proto='static'
network.loopback.ipaddr='127.0.0.1'
network.loopback.netmask='255.0.0.0'
network.globals=globals
network.globals.ula_prefix='XXXX'
network.lan=interface
network.lan.type='bridge'
network.lan.ifname='eth0'
network.lan.proto='static'
network.lan.netmask='255.255.255.0'
network.lan.igmp_snooping='1'
network.lan.ipaddr='XXXX'
network.lan_dev=device
network.lan_dev.name='eth0'
network.lan_dev.macaddr='XXXX'
network.wan=interface
network.wan.ifname='eth1'
network.wan.proto='static'
network.wan.ipaddr='XXXX'
network.wan.netmask='255.255.255.0'
network.wan.gateway='XXXX'
network.wan.broadcast='XXXX'
network.wan_dev=device
network.wan_dev.name='eth1'
network.wan_dev.macaddr='XXXX'
network.@switch[0]=switch
network.@switch[0].name='switch0'
network.@switch[0].reset='1'
network.@switch[0].enable_vlan='1'
network.@switch_vlan[0]=switch_vlan
network.@switch_vlan[0].device='switch0'
network.@switch_vlan[0].vlan='1'
network.@switch_vlan[0].ports='1 2 3 4 0'

uci show wireless:

wireless.radio0=wifi-device
wireless.radio0.type='mac80211'
wireless.radio0.hwmode='11g'
wireless.radio0.path='platform/soc/a000000.wifi'
wireless.radio0.htmode='HT20'
wireless.radio0.country='GB'
wireless.radio0.channel='auto'
wireless.radio0.legacy_rates='0'
wireless.default_radio0=wifi-iface
wireless.default_radio0.device='radio0'
wireless.default_radio0.network='lan'
wireless.default_radio0.mode='ap'
wireless.default_radio0.encryption='psk2+ccmp'
wireless.default_radio0.key='XXXX'
wireless.default_radio0.ssid='XXXX'
wireless.radio1=wifi-device
wireless.radio1.type='mac80211'
wireless.radio1.hwmode='11a'
wireless.radio1.path='platform/soc/a800000.wifi'
wireless.radio1.htmode='VHT80'
wireless.radio1.channel='auto'
wireless.radio1.country='GB'
wireless.radio1.legacy_rates='0'
wireless.default_radio1=wifi-iface
wireless.default_radio1.device='radio1'
wireless.default_radio1.network='lan'
wireless.default_radio1.mode='ap'
wireless.default_radio1.ssid='XXXX'
wireless.default_radio1.encryption='psk2+ccmp'
wireless.default_radio1.key='XXXX'

uci show firewall

firewall.@defaults[0]=defaults
firewall.@defaults[0].syn_flood='1'
firewall.@defaults[0].input='ACCEPT'
firewall.@defaults[0].output='ACCEPT'
firewall.@defaults[0].forward='ACCEPT'
firewall.@zone[0]=zone
firewall.@zone[0].name='lan'
firewall.@zone[0].input='ACCEPT'
firewall.@zone[0].output='ACCEPT'
firewall.@zone[0].forward='ACCEPT'
firewall.@zone[0].network='lan'
firewall.@zone[1]=zone
firewall.@zone[1].name='wan'
firewall.@zone[1].output='ACCEPT'
firewall.@zone[1].network='wan'
firewall.@zone[1].input='ACCEPT'
firewall.@zone[1].forward='ACCEPT'
firewall.@zone[2]=zone
firewall.@zone[2].name='vpn'
firewall.@zone[2].output='ACCEPT'
firewall.@zone[2].network='wg0'
firewall.@zone[2].mtu_fix='1'
firewall.@zone[2].input='DROP'
firewall.@zone[2].forward='DROP'
firewall.@zone[2].masq='1'
firewall.@zone[3]=zone
firewall.@zone[3].name='vpn1'
firewall.@zone[3].output='ACCEPT'
firewall.@zone[3].network='wg1'
firewall.@zone[3].input='DROP'
firewall.@zone[3].forward='DROP'
firewall.@zone[3].masq='1'
firewall.@zone[3].mtu_fix='1'
firewall.@forwarding[0]=forwarding
firewall.@forwarding[0].dest='vpn'
firewall.@forwarding[0].src='lan'
firewall.@forwarding[1]=forwarding
firewall.@forwarding[1].dest='wan'
firewall.@forwarding[1].src='lan'
firewall.@forwarding[2]=forwarding
firewall.@forwarding[2].dest='vpn1'
firewall.@forwarding[2].src='lan'
4

A few remarks:

  1. ULA prefix, LAN IP address, possibly WAN IP address are private and there is no fear of posting them here.
  2. You can delete the wan.broadcast address. It is calculated automatically anyway and people sometimes tend to have it wrong.
  3. Do you need the lan.igmp_snooping ?
  4. Avoid using auto channels in wireless. Pick yourself a "clean" channel and configure it.
5

Well, none of those things could have caused what I'm seeing (the wan.broadcast is correct, though I've now deleted it), igmp_snooping I've tried turning on and off to see if it caused an issue and it doesn't. So I'm guessing it's something else.