# Connect to ethernet devices through WiFi access point **URL:** \ **Category:** Product support\ **Created:** [August 13, 2020, 7:42am UTC](https://forums.balena.io/t/connect-to-ethernet-devices-through-wifi-access-point/172894 "2020-08-13T07:42:07Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![MrBlenny](https://sea2.discourse-cdn.com/balena/user_avatar/forums.balena.io/mrblenny/32/4229_2.png) [@MrBlenny](https://forums.balena.io/u/MrBlenny)\ **Post date:** [August 13, 2020, 7:42am UTC](https://forums.balena.io/t/connect-to-ethernet-devices-through-wifi-access-point/172894/1 "2020-08-13T07:42:07Z")
I have a device with a WiFi access point (USB dongle) and an ethernet port that connects to a switch and then lots of other devices. I want my balena device to to DHCP and DNS for all ethernet AND WiFi clients. I could not figure out how to put 2 different interfaces on the same subnet so I have a subnet with dnsmasq instance for each interface. ## WiFi AP config: ```auto [connection] id=balena-hotspot uuid=36060c57-aebd-4ccf-aba4-ef75121b5f77 type=wifi autoconnect=true interface-name=wlp0s20u4 permissions= secondaries= [wifi] band=bg mac-address-blacklist= mac-address-randomization=0 mode=ap seen-bssids= ssid=somehotspotssid [wifi-security] group= key-mgmt=wpa-psk pairwise= proto=rsn psk=some-password [ipv4] address1=10.42.0.1/24 dns=127.0.0.1; dns-search= method=manual [ipv6] addr-gen-mode=stable-privacy dns-search= method=auto ``` ```auto dnsmasq \ --address=/#/10.42.0.1 \ --dhcp-range=10.42.0.1,10.42.0.254 \ --dhcp-option=option:router,10.42.0.1 \ --interface=wlp0s20u4 \ --bind-interfaces \ --except-interface=lo \ --conf-file \ --no-hosts \ --log-facility=- ``` ## Ethernet ```auto [connection] id=pci-eth-1 type=ethernet interface-name=enp3s0 permissions= secondaries= [ethernet] mac-address-blacklist= [ipv4] address1=192.168.30.1/24 dns=127.0.0.1; dns-search= method=manual [ipv6] addr-gen-mode=stable-privacy dns-search= method=auto ``` ```auto dnsmasq \ --address=/#/192.168.30.1 \ --dhcp-range=192.168.30.1,192.168.30.254 \ --dhcp-option=option:router,192.168.30.1 \ --interface=enp3s0 \ --bind-interfaces \ --except-interface=lo \ --conf-file \ --no-hosts \ --log-facility=- ``` ## The issue When I connect to the WiFi AP, dnsmasq on the balena device will allocate a 10.42.0.X IP. Unfortunatley I cannot then ping any ethernet device running on 192.168.30.X. Similarly, ethernet devices cannot ping WiFI devices. ## Possible solutions? - If there some way to only have 1 dnsmasq instance that manages both the eth and wifi interfaces? Then I would not need to communicate accross two subnets. - Can I create some sort of bridge between these two subnets so every device can access every other device? Thanks so much for any advice! 🙂 ---
**Author:** ![majorz](https://sea2.discourse-cdn.com/balena/user_avatar/forums.balena.io/majorz/32/639_2.png) [@majorz](https://forums.balena.io/u/majorz)\ **Post date:** [August 13, 2020, 1:38pm UTC](https://forums.balena.io/t/connect-to-ethernet-devices-through-wifi-access-point/172894/6 "2020-08-13T13:38:15Z")
Hi, so you basically want to have a router-like setup with the Ethernet and WiFi interfaces serving clients on a single network. I have never tried such setup myself and I am not sure how well NetworkManager will support this, but you will need to aggregate the interfaces with a bridge. I see in some examples I googled `bridge.stp` is set to `no` - you can check whether this should apply to you. You can create a new bridge profile with `type=bridge`, `interface-name=br0` and `id=br0`. If you run `nmcli con add ifname br0 type bridge con-name br0` that will create a profile for you in `/etc/NetworkManager/system-connections` that you can edit. In that profile define a `method=manual` in the `[ipv4]` section, and `method=ignore` in the `[ipv6]` section. Then assign a static address like you do in your profiles above. Then in your WiFi and Ethernet profiles remove completely their `[ipv4]` and `[ipv6]` sections. Then add `master=br0` and `slave-type=bridge` in their `[connection]` section. After you setup the bridge to aggregate the two interfaces you can try running a single dnsmasq on top of the bridge interface similarly to how you are doing that currently. I have not tried that myself, but in theory that should work. As for your second question with your current setup with two subnets I do not think you need to add a bridge. If you cannot ping devices from one subnet to the other please try running `iptables -P FORWARD ACCEPT` in the host OS. When a packet with unknown IP is sent from a device, it will be forwarded to the default gateway (in your case this device with the two interfaces) - then the kernel will know that it needs to forward it to a device on the other subnet. The above iptables command changes the default forwarding policy from DROP to ACCEPT, so that this can happen. I will be on vacation till the middle of next week starting from tomorrow, so I may not be able to respond till I get back if you have some feedback here, but my colleagues will look into it and respond if they have an answer. Thanks a lot, Zahari ---
**Author:** ![MrBlenny](https://sea2.discourse-cdn.com/balena/user_avatar/forums.balena.io/mrblenny/32/4229_2.png) [@MrBlenny](https://forums.balena.io/u/MrBlenny)\ **Post date:** [August 14, 2020, 1:24am UTC](https://forums.balena.io/t/connect-to-ethernet-devices-through-wifi-access-point/172894/8 "2020-08-14T01:24:22Z")
Thanksso much for your help @majorz ! I’ve made those changes. Should I be running dnsmasq on the bridge ot the two interfaces, i.e. `dnsmasq --interface=br0 ...` or `dnsmasq --interface=enp3s0 --interface=wlp0s20u4`. In either case I’m getting an `dnsmasq: unknown interface br0` style error. These two connections and the bridge are now marked as disconnected in nmcli. I tried adding `autoconnect=true` to no avail. The hotspot SSID is no longer visible on the network - I assume this is the result of removing the `[ipv4]` settings. ```auto root@balena:~# nmcli wlp2s0: connected to balena-hotspot-2 "wlp2s0" wifi (rtl8821ae), DC:85:DE:E7:C2:9D, hw, mtu 1500 inet4 10.43.0.1/24 route4 10.43.0.0/24 inet6 fe80::8c3c:2ad1:5bee:98e5/64 route6 fe80::/64 route6 ff00::/8 supervisor0: connected to supervisor0 "supervisor0" bridge, 02:42:A0:B3:27:20, sw, mtu 1500 inet4 10.114.104.1/25 route4 10.114.104.0/25 enp3s0: disconnected "enp3s0" 1 connection available ethernet (r8169), FC:AA:14:DF:A1:41, hw, mtu 1500 wlp0s20u4: disconnected "Ralink n" 1 connection available wifi (rt2800usb), 9C:EF:D5:FB:C1:D4, hw, mtu 1500 balena0: unmanaged "balena0" bridge, 02:42:68:75:60:7D, sw, mtu 1500 br-255c7c989811: unmanaged "br-255c7c989811" bridge, 02:42:01:0D:98:82, sw, mtu 1500 br0: unmanaged "br0" bridge, DA:4B:0A:EA:C2:EE, sw, mtu 1500 resin-dns: unmanaged "resin-dns" bridge, 62:5B:D4:33:38:66, sw, mtu 1500 veth43fe36f: unmanaged "veth43fe36f" ethernet (veth), 7E:AF:EE:41:60:B5, sw, mtu 1500 veth45faec8: unmanaged "veth45faec8" ethernet (veth), 8A:91:C1:8E:3F:80, sw, mtu 1500 veth70a49ac: unmanaged "veth70a49ac" ethernet (veth), 1E:31:E8:F1:7A:11, sw, mtu 1500 vetha8a8d35: unmanaged "vetha8a8d35" ethernet (veth), 16:D4:E7:CA:1A:F1, sw, mtu 1500 vethb53ee17: unmanaged "vethb53ee17" ethernet (veth), 1E:C5:76:F4:A7:F0, sw, mtu 1500 vethd45be50: unmanaged "vethd45be50" ethernet (veth), 52:AE:84:5F:19:23, sw, mtu 1500 sit0: unmanaged "sit0" iptunnel (sit), sw, mtu 1480 lo: unmanaged "lo" loopback (unknown), 00:00:00:00:00:00, sw, mtu 65536 ``` ---
**Author:** ![mtoman](https://sea2.discourse-cdn.com/balena/user_avatar/forums.balena.io/mtoman/32/3599_2.png) [@mtoman](https://forums.balena.io/u/mtoman)\ **Post date:** [August 14, 2020, 11:12am UTC](https://forums.balena.io/t/connect-to-ethernet-devices-through-wifi-access-point/172894/9 "2020-08-14T11:12:57Z")
Hi, the `br0: unmanaged` is suspicious, NetworkManager should bring it up and enable both `wlp0s20u4` and `enp3s0` as `br0` is their master. Could you please share the config file you are using for `br0`? Also do you see the `br0` interface running a simple `ip addr` command? Thanks