Skip to main content

Wi-Fi Access Point

Use these steps to turn the Omega4 into a WPA2 access point on a dedicated wlan network and advertise the board hostname as the SSID.

1. Capture the hostname (SSID seed)​

cat /proc/sys/kernel/hostname

Copy the value (for example, Omega-A7FE). It will become the SSID.

2. Configure the radio for AP mode on wlan​

Convert radio0 into an AP, attach it to network wlan, and set the WPA2 key:

uci set wireless.radio0.disabled='0'
uci set wireless.default_radio0.mode='ap'
uci set wireless.default_radio0.disabled='0'
uci set wireless.default_radio0.network='wlan'
uci set wireless.default_radio0.ssid="$(cat /proc/sys/kernel/hostname)"
uci set wireless.default_radio0.encryption='psk2'
uci set wireless.default_radio0.key='12345678'   # replace with your PSK
uci commit wireless

3. Set the device IP to 192.168.4.1​

If you want the Omega4 to act as a standalone AP with a known management address, create a wlan interface and set it to 192.168.4.1/24:

uci set network.wlan=interface
uci set network.wlan.proto='static'
uci set network.wlan.ipaddr='192.168.4.1'
uci set network.wlan.netmask='255.255.255.0'
uci commit network
/etc/init.d/network restart
caution

Changing the management subnet can disconnect your current SSH session. If you are connected over Ethernet and your PC is on a different subnet, you will need to reconfigure your PC to 192.168.4.x (or reconnect over Wi‑Fi after DHCP is enabled below).

4. Enable the DHCP server​

Serve client addresses on wlan (and therefore on Wi‑Fi, since it is attached to network wlan) using dnsmasq:

uci set dhcp.wlan=dhcp
uci set dhcp.wlan.interface='wlan'
uci set dhcp.wlan.ignore='0'
uci set dhcp.wlan.start='100'
uci set dhcp.wlan.limit='150'
uci set dhcp.wlan.leasetime='12h'
uci commit dhcp
/etc/init.d/dnsmasq restart
About htmode (channel width)

In OpenWrt, htmode sets the Wi‑Fi “PHY mode” and channel width. The suffix (20/40/80) is the channel width in MHz:

  • HT20 / HT40: 802.11n (High Throughput).
  • VHT20 / VHT40 / VHT80: 802.11ac (Very High Throughput, 5 GHz).
  • HE20 / HE40 / HE80: 802.11ax (High Efficiency) if your wpad/hostapd build supports it.

Wider channels can increase the negotiated link rate, but they also use more spectrum and are more sensitive to interference. On crowded 2.4 GHz networks, HT20 is often more stable (and sometimes faster in real throughput) than HT40.

Omega4 note: the Wi‑Fi module is connected over SDIO 2.0, which supports up to 400 Mbps on the bus. Even if the link rate shows higher values (for example on VHT80), real throughput will be limited by the SDIO link and protocol overhead.

5. Force an 802.11n/HT40 channel​

Current wpad builds do not handle 802.11ax HE options, so keep the radio on 2.4 GHz HT40:

uci set wireless.radio0.he='0'
uci set wireless.radio0.htmode='HT40'
uci set wireless.radio0.channel='1'   # choose any valid 2.4 GHz channel
uci commit wireless

Optional: switch to 5 GHz AP​

The same radio can serve a 5 GHz AP (one band at a time). Pick a non-DFS channel to avoid radar waits and keep HE disabled:

uci set wireless.radio0.band='5g'
uci set wireless.radio0.channel='36'   # choose a legal channel for your country
uci set wireless.radio0.htmode='VHT40' # try VHT80 if you have clean spectrum and it’s stable
uci set wireless.radio0.he='0'
uci set wireless.radio0.country='US'   # replace with your two-letter country code
uci commit wireless

Run wifi reload after switching bands; the SSID, key, and wlan network stay the same.

info

If logread shows hostapd errors like unknown configuration item 'ieee80211ac', the installed wpad build is missing 802.11ac support. Fix by installing a full build (for example wpad-basic/wpad-openssl) or drop the channel width to HT40/HT20 on 5 GHz to avoid VHT options.

6. Apply and start Wi-Fi​

wifi reload            # rebuilds hostapd config and restarts the radio
ifconfig phy0-ap0 up   # only if the interface stays DOWN after reload

7. Validate the AP​

  • wifi status reports radio0 up with your chosen channel/htmode and interface phy0-ap0.
  • ubus call network.interface.wlan status shows up: true and 192.168.4.1 under ipv4-address.
  • iwinfo phy0-ap0 info shows Mode: Master, the expected SSID, and the same channel/width.
  • ifconfig phy0-ap0 lists the interface as UP ... RUNNING.
  • logread | grep hostapd ends with phy0-ap0: AP-ENABLED.

8. Troubleshooting (AP interface not up)​

If phy0-ap0 never appears or stays DOWN after wifi reload:

wifi status
logread | grep -E "hostapd|wpad|netifd|cfg80211"
uci show wireless.radio0
uci show wireless.default_radio0
uci show network.wlan

Common causes:

  • Missing AP support: ensure a wpad/hostapd package is installed (otherwise wifi reload cannot start the AP).
  • Single radio: if STA mode is enabled, the AP interface may be disabled; set wireless.default_radio0.mode='ap' and reload.
  • Bad channel/regdomain: set wireless.radio0.country to your country code and try a different channel, then wifi reload.

Clients can now join SSID <hostname> (for example, Omega-A7FE) using the configured WPA2 key. Traffic will be on network wlan, so ensure wlan is configured with DHCP or static addressing as needed.

Tested on Omega-A7FE: wifi status shows radio0 up with SSID Omega-A7FE, phy0-ap0 is up in AP mode, and hostapd reports AP-ENABLED.