balena-supervisor/docs/configurations.md
Felipe Lalanne d5cc8238cb Add information about hdmi port 2 config vars
Support for colon characters was added v14.6.0 which enabled
configurations for HDMI port 2 (e.g on the RPi 4). These configurations
are not documented anywhere else so this allows users to be able to
better find the relevant information for working with HDMI.

Change-type: patch
Relates-to: #2090
2023-05-08 15:21:28 -04:00

19 KiB

Configuration Variables

Configuration variables allow you to provide runtime configuration to the host OS and Supervisor. These variables all begin with BALENA_ or the legacy prefix RESIN_. Beginning with Supervisor v7.0.0, a number of them automatically will be sent to the cloud on provision.

Note: Configuration variables defined in the dashboard will not apply to devices in local mode.

This list contains configuration variables that can be used with all balena devices, some of which will automatically appear for devices with Supervisor v7.0.0 and greater. While they may not automatically populate in the dashboard, most of these variables can still be used with older Supervisor versions, so be sure to check the Valid from column:

Name Type Reboots Default Description Valid from
BALENA_SUPERVISOR_OVERRIDE_LOCK boolean false false Override any existing locks preventing any changes to the app. v1.0.0
BALENA_SUPERVISOR_VPN_CONTROL boolean false true Enable / Disable VPN service on device. v1.1.0
BALENA_SUPERVISOR_CONNECTIVITY_CHECK boolean false true Enable / Disable VPN connectivity check v1.3.0
BALENA_SUPERVISOR_LOG_CONTROL boolean false true Enable / Disable logs being sent to the balena API v1.3.0
BALENA_SUPERVISOR_POLL_INTERVAL integer false 600000 Define the balena API poll interval in milliseconds. This value can increase if the device needs to backoff due to server errors. The minimum value for this variable is defined by the balenaCloud backend, and may vary. v1.3.0
BALENA_SUPERVISOR_DELTA_REQUEST_TIMEOUT integer false 30000 Millisecond time within which an HTTP response containing delta metadata must be returned by the delta server. v2.9.0
BALENA_SUPERVISOR_LOCAL_MODE boolean false false Enable / Disable local mode. v4.0.0
BALENA_SUPERVISOR_DELTA_APPLY_TIMEOUT integer false 0 Millisecond time within which delta data will begin syncing to the local device. v6.2.0
BALENA_SUPERVISOR_DELTA_RETRY_COUNT integer false 30 Number of retry attempts for downloading deltas. v6.2.0
BALENA_SUPERVISOR_DELTA_RETRY_INTERVAL integer false 10000 Millisecond time before another delta download is attempted after failiure. v6.2.0
BALENA_SUPERVISOR_DELTA_VERSION integer false 3 Specifies the delta version to use which has different APIs and download algorithms. v7.9.0
BALENA_SUPERVISOR_PERSISTENT_LOGGING boolean true false Persists journal logs to disk so they will be available after a reboot event. v7.15.0
BALENA_SUPERVISOR_INSTANT_UPDATE_TRIGGER boolean false true Enable / Disable instant triggering of updates when a new release is deployed. If set to false, the device will ignore the notification that is triggered when the device's target state has changed. In this case, the device will rely on polling to apply updates. Coupled with a large BALENA_SUPERVISOR_POLL_INTERVAL, this allows spreading out updates in large fleets to avoid overloading local networks when there is a large number of devices at one location. v9.13.0
BALENA_HOST_FIREWALL_MODE string false off Toggle firewall modes between on, off, and auto. v11.9.1
BALENA_HOST_DISCOVERABILITY boolean false true Enable / Disable Avahi to run which will allow the device to respond to requests such as network scans. v11.9.2
BALENA_HOST_SPLASH_IMAGE integer true /boot/splash/balena-logo-default.png Allows changing splash screen on boot to user defined file from userspace. v12.3.0
BALENA_SUPERVISOR_HARDWARE_METRICS boolean false true Toggle hardware metrics reporting to the cloud, which occurs every 10 seconds when there are changes. Metrics include CPU utilization, CPU temperature, memory usage, and disk space. Useful for devices with bandwidth sensitivity. v12.8.0

In addition to these values, there may be some device-type specific configuration variables that can be set.

Config.txt

Supported boards: Any Raspberry Pi and balenaFin.

This device type utilizes a config.txt file of which we offer some values to be configured. The following values are not all the configurations found in the config.txt file and are just balena additions or edits to the OEM version.

Name Type Reboots Default Description Valid from
BALENA_HOST_CONFIG_dtoverlay string true "vc4-fkms-v3d" Allows loading custom device tree overlays. v1.0.0
BALENA_HOST_CONFIG_device_tree_overlay string true "vc4-fkms-v3d" Allows loading custom device tree overlays. v1.0.0
BALENA_HOST_CONFIG_dtparam string true "i2c_arm=on","spi=on","audio=on" Allows setting parameters for the default overlay. v1.0.0
BALENA_HOST_CONFIG_device_tree_param string true "i2c_arm=on","spi=on","audio=on" Allows setting parameters for the default overlay. v1.0.0
BALENA_HOST_CONFIG_disable_splash integer true 1 Enable / Disable the splash screen to display image on boot. v1.0.0
BALENA_HOST_CONFIG_gpu_mem integer true 16 Define device GPU memory in megabytes. v1.0.0
BALENA_HOST_CONFIG_gpio string true undefined Allows GPIO pins to be set to specific modes and values at boot time. See here for more. v1.0.0
BALENA_HOST_CONFIG_hdmi_force_hotplug:1 number true undefined Force the HDMI hotplug signal on HDMI port 2. See here for more. v14.6.0
BALENA_HOST_CONFIG_hdmi_group:1 number true undefined Define the HDMI output group on HDMI port 2. See here for more. v14.6.0
BALENA_HOST_CONFIG_hdmi_mode:1 number true undefined Define the HDMI output format on HDMI port 2. See here for more. v14.6.0

ConfigFS

Supported boards: UP Board

This device type utilizes a configFS file interface that allows definition of arbitrary functions and configurations.

Name Type Reboots Default Description Valid from
BALENA_HOST_CONFIGFS_ssdt string true undefined Allows configuring a user defined SSDTs from userspace via the configfs interface. See SSDT Overlays. v10.9.2

Extra-uEnv

Supported boards: Nvidia Jetson Nano and TX2.

This device type utilizes a file which we created to proxy configurations to extlinux.conf.

Name Type Reboots Default Description Valid from
BALENA_HOST_EXTLINUX_isolcpus string true undefined Allows to isolate CPU cores from kernel scheduler. See kernel parameters. v7.10.0
BALENA_HOST_EXTLINUX_fdt string true undefined Specify a filename with extension from userspace to use as DTB. See Device Tree Binary. v11.9.0

ODMDATA

Supported boards: Nvidia Jetson TX2.

This device type utilizes a configurable hardware partition to set the mode for UPHY lane assigment.

Name Type Reboots Default Description Valid from
BALENA_HOST_CONFIG_odmdata_configurations integer true 2 Select with mode to configure UPHY lanes. See UPHY lane assignment. v11.13.0