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EMCON & radio control

An AryaOS box has two onboard radios that emit RF: Wi-Fi (the aryaos-xxxx onboarding hotspot, and any Wi-Fi client link) and Bluetooth (the PAN onboarding path). For low-probability-of-intercept / low-probability-of-detection (LPI/LPD) operation you often want to silence them - or just turn off the Wi-Fi hotspot once a unit is fielded on ethernet. The aryaos-radio helper and The Radios controls in Cockpit > AryaOS Site do both.

Wired ethernet is never affected

EMCON and the AP controls only touch the onboard radios. The wired ethernet link keeps working, so a box you reach over ethernet (or Tailscale over ethernet) stays reachable.

Disable the Wi-Fi hotspot

Once a box is fielded on Ethernet, you can stop it from broadcasting aryaos-xxxx at all. Disabling the hotspot stops the broadcast and keeps it off across reboots.

AryaOS Site > Radios > Wi-Fi hotspot > Disable. Re-enable from the same card.

sudo aryaos-radio ap off      # stop the aryaos-xxxx broadcast (persists across reboot)
sudo aryaos-radio ap on       # bring it back
sudo aryaos-radio ap status

The Wi-Fi radio itself stays available (e.g. to join a Wi-Fi network as a client). Only the onboarding hotspot is turned off. To silence the radio entirely, use EMCON below.

EMCON (radio silence)

EMCON blocks both Wi-Fi and Bluetooth at the rfkill level, so the onboard radios stop transmitting entirely. The block persists across reboots. aryaos-radio-silence.service applies /etc/aryaos/emcon before the network starts. Thus, an EMCON device emits no RF during boot.

AryaOS Site > Radios > EMCON / radio silence > On. The hotspot drops and The Wi-Fi/Bluetooth adapters go dark. Toggle Off to restore.

sudo aryaos-radio silence on      # rfkill-block Wi-Fi + Bluetooth (persists)
sudo aryaos-radio silence off     # unblock and restore the hotspot
sudo aryaos-radio silence status  # show EMCON flag + rfkill state

SDR receivers are not silenced by EMCON

Software-defined radios (ADS-B/AIS/drone dongles) are receive-only - they do not transmit, so they present no emissions signature and EMCON leaves them running. If you want them powered down anyway, stop their services (e.g. sudo systemctl stop adsbcot dronecot) or unplug them.

Hotspot clients cannot reach the wired network

Independent of EMCON, AryaOS never bridges or routes a wireless onboarding client onto the wired ethernet. The firewalld default zone ships with no intra-zone forwarding. A hotspot or Bluetooth PAN client can reach the device's onboarding and administration services. The firewall never routes that client to eth0 or the upstream network. This rule also applies when the host enables net.ipv4.ip_forward. See Firewall for the zone details.