Drone Agent systemd services

The agent runs as a set of systemd units, one per job: MAVLink, video, radio, cloud, logging and so on. The supervisor (ados-supervisor, a native Rust orchestrator) starts, watches and restarts the other units through systemd. Every long-running unit runs inside the ados.slice cgroup. The unit names are a stable interface: you type the same systemctl restart ados-<name> whichever language a unit runs. This page is the canonical unit list. For why the services are split this way, see Agent services.

Units by profile

Which units run is decided by the node profile (and, on a ground station, the mesh role), not by the board. See Node profiles.

drone
ground_station
workstation and compute

Unit	Description	Category
`ados-api`	ADOS REST API	core
`ados-camera-probe`	ADOS camera presence probe (apply-verify-auto-revert)	n/a
`ados-cloud`	ADOS Cloud Relay (MQTT + Convex Heartbeat)	core
`ados-control`	ADOS Native Control API	on_demand
`ados-crsf`	ADOS CRSF RC Control Lane	hardware
`ados-display-probe`	ADOS display presence probe (apply-verify-auto-revert)	n/a
`ados-fbcon-detach`	ADOS detach framebuffer console from the LCD framebuffer	n/a
`ados-gpio`	ADOS GPIO Output Service (status buzzer / LED)	hardware
`ados-logd`	ADOS Logging and Telemetry Store	core
`ados-mavlink`	ADOS MAVLink Proxy	core
`ados-plugin-host`	ADOS Plugin Host	n/a
`ados-power`	ADOS Power Hardening Re-assert	n/a
`ados-supervisor`	ADOS Drone Agent Supervisor	n/a
`ados-swarmbus`	ADOS Swarm State Bus	core
`ados-tunnel-config`	ADOS Config-over-Radio Channel	hardware
`ados-usb-otg-host`	ADOS force USB OTG controllers into host mode	n/a
`ados-video`	ADOS Video Pipeline	hardware
`ados-vision-hailo`	ADOS Vision NPU Inference Sidecar (Hailo)	hardware
`ados-vision-rknn`	ADOS Vision NPU Inference Sidecar (RKNN)	hardware
`ados-vision`	ADOS Vision Engine	hardware
`ados-wfb`	ADOS WFB-ng Link Manager	hardware

Unit	Description	Category
`ados-api`	ADOS REST API	core
`ados-batman`	ADOS batman-adv local wireless mesh (ground-station mesh role)	hardware
`ados-camera-probe`	ADOS camera presence probe (apply-verify-auto-revert)	n/a
`ados-cloud`	ADOS Cloud Relay (MQTT + Convex Heartbeat)	core
`ados-control`	ADOS Native Control API	on_demand
`ados-crsf`	ADOS CRSF RC Control Lane	hardware
`ados-display-probe`	ADOS display presence probe (apply-verify-auto-revert)	n/a
`ados-dnsmasq-gs`	ADOS Ground Station DHCP/DNS (dnsmasq)	hardware
`ados-fbcon-detach`	ADOS detach framebuffer console from the LCD framebuffer	n/a
`ados-gpio`	ADOS GPIO Output Service (status buzzer / LED)	hardware
`ados-hostapd`	ADOS Ground Station WiFi AP (hostapd)	hardware
`ados-input`	ADOS Input Manager (ground-station profile)	hardware
`ados-kiosk`	ADOS HDMI Kiosk (ground-station profile)	hardware
`ados-logd`	ADOS Logging and Telemetry Store	core
`ados-mavlink`	ADOS MAVLink Proxy	core
`ados-mediamtx-gs`	ADOS ground-station media server (mediamtx)	hardware
`ados-mesh-pairing`	ADOS mesh pairing daemon (UDP 5801 sidecar for pairing_manager)	n/a
`ados-oled-i2c`	ADOS I2C status OLED (ground-station profile)	hardware
`ados-oled`	ADOS OLED UI (ground-station profile)	hardware
`ados-pic`	ADOS Pilot-in-Command Arbiter (ground-station profile)	hardware
`ados-plugin-host`	ADOS Plugin Host	n/a
`ados-power`	ADOS Power Hardening Re-assert	n/a
`ados-setup-captive`	ADOS Captive Portal DNS + HTTP responder (first-boot only)	on_demand
`ados-supervisor`	ADOS Drone Agent Supervisor	n/a
`ados-swarmbus`	ADOS Swarm State Bus	core
`ados-tunnel-config`	ADOS Config-over-Radio Channel	hardware
`ados-uplink-router`	ADOS Uplink Router (ground-station profile)	hardware
`ados-usb-otg-host`	ADOS force USB OTG controllers into host mode	n/a
`ados-wfb-receiver`	ADOS WFB-ng receiver (mesh receiver role)	hardware
`ados-wfb-relay`	ADOS WFB-ng relay (mesh relay role)	hardware
`ados-wfb-rx`	ADOS WFB-ng RX (ground-station direct role)	hardware

Unit	Description	Category
`ados-api`	ADOS REST API	core
`ados-camera-probe`	ADOS camera presence probe (apply-verify-auto-revert)	n/a
`ados-cloud`	ADOS Cloud Relay (MQTT + Convex Heartbeat)	core
`ados-control`	ADOS Native Control API	on_demand
`ados-display-probe`	ADOS display presence probe (apply-verify-auto-revert)	n/a
`ados-fbcon-detach`	ADOS detach framebuffer console from the LCD framebuffer	n/a
`ados-gpio`	ADOS GPIO Output Service (status buzzer / LED)	hardware
`ados-logd`	ADOS Logging and Telemetry Store	core
`ados-plugin-host`	ADOS Plugin Host	n/a
`ados-power`	ADOS Power Hardening Re-assert	n/a
`ados-supervisor`	ADOS Drone Agent Supervisor	n/a
`ados-usb-otg-host`	ADOS force USB OTG controllers into host mode	n/a

Each installed extension also runs as its own ados-plugin-… unit, on every profile. The unit name carries the extension id and a short hash. See Extensions.

Every unit

The full table, with the API restart permission, whether a restart drops the vehicle link, and each unit’s memory cap (MemoryMax):

Unit	Description	Category	Profiles	Restartable via API	Drops link	Memory cap
`ados-api`	ADOS REST API	core	drone, ground_station, workstation, compute	Yes	No	128M
`ados-batman`	ADOS batman-adv local wireless mesh (ground-station mesh role)	hardware	ground_station	Yes	Yes	64M
`ados-camera-probe`	ADOS camera presence probe (apply-verify-auto-revert)	n/a	drone, ground_station, workstation, compute	No	No	n/a
`ados-cloud`	ADOS Cloud Relay (MQTT + Convex Heartbeat)	core	drone, ground_station, workstation, compute	Yes	Yes	256M
`ados-control`	ADOS Native Control API	on_demand	drone, ground_station, workstation, compute	No	No	384M
`ados-crsf`	ADOS CRSF RC Control Lane	hardware	drone, ground_station	Yes	Yes	64M
`ados-display-probe`	ADOS display presence probe (apply-verify-auto-revert)	n/a	drone, ground_station, workstation, compute	No	No	n/a
`ados-dnsmasq-gs`	ADOS Ground Station DHCP/DNS (dnsmasq)	hardware	ground_station	Yes	Yes	32M
`ados-fbcon-detach`	ADOS detach framebuffer console from the LCD framebuffer	n/a	drone, ground_station, workstation, compute	No	No	n/a
`ados-gpio`	ADOS GPIO Output Service (status buzzer / LED)	hardware	drone, ground_station, workstation, compute	Yes	No	32M
`ados-hostapd`	ADOS Ground Station WiFi AP (hostapd)	hardware	ground_station	Yes	Yes	32M
`ados-input`	ADOS Input Manager (ground-station profile)	hardware	ground_station	Yes	Yes	n/a
`ados-kiosk`	ADOS HDMI Kiosk (ground-station profile)	hardware	ground_station	Yes	No	n/a
`ados-logd`	ADOS Logging and Telemetry Store	core	drone, ground_station, workstation, compute	Yes	No	256M
`ados-mavlink`	ADOS MAVLink Proxy	core	drone, ground_station	Yes	Yes	50M
`ados-mediamtx-gs`	ADOS ground-station media server (mediamtx)	hardware	ground_station	Yes	Yes	256M
`ados-mesh-pairing`	ADOS mesh pairing daemon (UDP 5801 sidecar for pairing_manager)	n/a	ground_station	Yes	No	48M
`ados-oled-i2c`	ADOS I2C status OLED (ground-station profile)	hardware	ground_station	Yes	No	48M
`ados-oled`	ADOS OLED UI (ground-station profile)	hardware	ground_station	Yes	No	48M
`ados-pic`	ADOS Pilot-in-Command Arbiter (ground-station profile)	hardware	ground_station	Yes	Yes	n/a
`ados-plugin-host`	ADOS Plugin Host	n/a	drone, ground_station, workstation, compute	Yes	No	n/a
`ados-power`	ADOS Power Hardening Re-assert	n/a	drone, ground_station, workstation, compute	Yes	No	n/a
`ados-setup-captive`	ADOS Captive Portal DNS + HTTP responder (first-boot only)	on_demand	ground_station	Yes	No	48M
`ados-supervisor`	ADOS Drone Agent Supervisor	n/a	drone, ground_station, workstation, compute	No	Yes	n/a
`ados-swarmbus`	ADOS Swarm State Bus	core	drone, ground_station	Yes	Yes	32M
`ados-tunnel-config`	ADOS Config-over-Radio Channel	hardware	drone, ground_station	Yes	No	64M
`ados-uplink-router`	ADOS Uplink Router (ground-station profile)	hardware	ground_station	Yes	Yes	96M
`ados-usb-otg-host`	ADOS force USB OTG controllers into host mode	n/a	drone, ground_station, workstation, compute	No	No	n/a
`ados-video`	ADOS Video Pipeline	hardware	drone	Yes	Yes	512M
`ados-vision-hailo`	ADOS Vision NPU Inference Sidecar (Hailo)	hardware	drone	Yes	No	512M
`ados-vision-rknn`	ADOS Vision NPU Inference Sidecar (RKNN)	hardware	drone	Yes	No	512M
`ados-vision`	ADOS Vision Engine	hardware	drone	Yes	No	256M
`ados-wfb-receiver`	ADOS WFB-ng receiver (mesh receiver role)	hardware	ground_station	Yes	Yes	96M
`ados-wfb-relay`	ADOS WFB-ng relay (mesh relay role)	hardware	ground_station	Yes	Yes	64M
`ados-wfb-rx`	ADOS WFB-ng RX (ground-station direct role)	hardware	ground_station	Yes	Yes	64M
`ados-wfb`	ADOS WFB-ng Link Manager	hardware	drone	Yes	Yes	96M

Notes on specific units:

ados-control is the HTTP front on port 8080 on every profile. The residual Python API (ados-api) runs behind it on an internal socket.
ados-logd ships masked; see Black Box. The supervisor starts it only when logging.store.enabled is on.
ados-hostapd runs hostapd directly. The access point it serves is configured by ados-net, which runs under ados-uplink-router.
ados-pic is the pilot-in-command arbiter on a ground station. It also reads the front-panel buttons.
ados-mediamtx-gs is the ground-side MediaMTX relay that serves received video to browsers.
Boot helpers. The units with no category in the table (ados-power, ados-usb-otg-host, ados-camera-probe, ados-display-probe and ados-fbcon-detach) are one-shot boot helpers. systemd runs them at boot; they are not in the supervisor’s registry.

The headless keep set

A lean headless node boots only the Rust core. Enable it with agent.headless: true in /etc/ados/config.yaml. The supervisor’s headless gate then permits exactly six units and blocks everything else, including ados-api: ados-mavlink, ados-swarmbus, ados-logd, ados-video, ados-wfb, ados-control. ados-control is in the set because it is the node’s only HTTP surface. ados-logd is in it because a lean flight node is the node an operator cannot reach, so it most needs its own flight recorder (it still runs only when the store is enabled).

Start order

The supervisor starts units by category: Core (for example mavlink, swarmbus, api, cloud, logd) → Hardware (video, wfb, vision, ground station units) → OnDemand (for example control). Hardware units start when their hardware is present; ados-video, for example, starts when a camera or a network video source is configured. Unit files add these orderings:

ados-video, ados-wfb, ados-cloud, ados-control and ados-plugin-host are After=ados-mavlink.service.
ados-control and ados-plugin-host are owned by systemd: the installer enables them and they start with the supervisor. The supervisor watches them but does not start them itself.
Units that can have nothing to do on a node (for example ados-swarmbus with no fleet slot, or ados-logd with the store off) exit 0 and stay idle instead of restarting.

Restart and crash loops

Units restart on their own:

[Service]
Restart=always
RestartSec=3

Most units also set StartLimitIntervalSec=0, so systemd never stops retrying them. Units that have nothing to do on this node exit 0 and stay parked instead of restarting (RestartPreventExitStatus=0). After 5 failures within 60 s the supervisor labels the unit crash_looping (visible in GET /api/services) and keeps retrying it on a fixed parked cadence, so it recovers when the cause clears.

curl http://localhost:8080/api/services \
  -H "X-ADOS-Key: $KEY"

See REST API for authentication.

Resource limits

Each unit runs with cgroup limits so one service cannot starve the rest. For example, ados-mavlink.service:

[Service]
MemoryMax=50M
CPUQuota=25%

The memory cap for every unit is in the Every unit table.

Dependencies on a ground station

The ground station units with explicit ordering:

ados-kiosk         After=ados-mediamtx-gs ados-control ados-api
ados-uplink-router After=NetworkManager.service
ados-dnsmasq-gs    After=ados-hostapd  Requires=ados-hostapd

Manage services

Check status

# All agent units
sudo systemctl list-units "ados-*" --all

# One unit
sudo systemctl status ados-video

Restart a service

sudo systemctl restart ados-video

View logs

The journal is the log of record.

# Last 50 lines from one unit
sudo journalctl -u ados-video -n 50

# Follow live
sudo journalctl -u ados-video -f

# All agent units together
sudo journalctl -u "ados-*" -f

# Since a time
sudo journalctl -u ados-mavlink --since "10 minutes ago"

Stop and start everything

sudo systemctl stop ados-supervisor
sudo systemctl start ados-supervisor

Stopping the supervisor stops the units it manages.

Unit files

The unit files are installed at:

/etc/systemd/system/ados-*.service

To read one:

systemctl cat ados-video

Do not edit the unit files directly. Upgrades overwrite them. To customize a unit (for example to add an environment variable or change a limit), use a drop-in override, which persists across upgrades:

sudo systemctl edit ados-video

Next steps

HAL and tiers

Board detection and the default tier.

Black Box

Turn on the durable logging store.

Drone Agent diagnostics

Check service health and the link.

Get started

Set up and use

Link, video and flight systems

Reference

Diagnose

Units by profile

Every unit

The headless keep set

Start order

Restart and crash loops

Resource limits

Dependencies on a ground station

Manage services

Check status

Restart a service

View logs

Stop and start everything

Unit files

Next steps

HAL and tiers

Black Box

Drone Agent diagnostics

​Units by profile

​Every unit

​The headless keep set

​Start order

​Restart and crash loops

​Resource limits

​Dependencies on a ground station

​Manage services

​Check status

​Restart a service

​View logs

​Stop and start everything

​Unit files

​Next steps

HAL and tiers

Black Box

Drone Agent diagnostics

Units by profile

Every unit

The headless keep set

Start order

Restart and crash loops

Resource limits

Dependencies on a ground station

Manage services

Check status

Restart a service

View logs

Stop and start everything

Unit files

Next steps