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Reference: memfaultctl CLI

Useful links:

Basic Usage

Running memfaultctl --help prints the following:

# memfaultctl -h
Usage: memfaultctl [OPTION] <COMMAND> ...

-c <config file> : Use configuration file
-h : Display this help and exit
-v : Show version information

enable-data-collection : Enable data collection and restart memfaultd
disable-data-collection : Disable data collection and restart memfaultd
enable-dev-mode : Enable developer mode and restart memfaultd
disable-dev-mode : Disable developer mode and restart memfaultd
reboot [--reason <n>] : Register reboot reason and call 'reboot'
request-metrics : Flush collectd metrics to Memfault now
show-settings : Show memfaultd settings
sync : Flush memfaultd queue to Memfault now
trigger-coredump [segfault|divide-by-zero] : Trigger a coredump and immediately reports it to Memfault (defaults to segfault)
write-attributes <VAR1=VAL1 ...> : Write device attribute(s) to Memfaultd

The --config-file path defaults to /etc/memfaultd.conf. The settings you add in /etc/memfaultd.conf extend the built-in configuration file.

Developer mode

Enabling developer mode will change some settings of memfaultd to make development and testing easier:

  • Coredumps will not be rate-limited on device. All crashes will be reported to Memfault immediately (queue is processed immediately);
  • write-attributes events will be flushed immediately to Memfault.

To enable developer mode, use memfaultctl enable-dev-mode. This setting will be persisted across reboots. To disable developer mode, use memfaultctl disable-dev-mode.

Server-side rate limiting will apply to the device you're using to work on the integration process. Once you can see the device on the Memfault Web App, consider enabling Server-Side Developer Mode for it on the Memfault Web App to temporarily bypass these limits.

memfaultctl commands


Call this command when your user has given consent to the collection of usage and performance information.

This setting is persisted across reboots and updates. To turn of collection, use memfaultctl disable-data-collection.


Call this command to enable developer mode (see above) on this system.

This setting is persisted across reboots and updates. To disable developer mode, use memfaultctl disable-dev-mode.


This command will write the provided reboot reason to the last_reboot_reason_file and restart the machine with the reboot command.


# memfaultctl reboot --reason 4

Refer to our list of reboot reasons.


This command will restart collectd (to trigger a data collection event) and then send a SIGUSR1 to flush the metrics to Memfault.


Prints the current configuration of memfaultd.


# memfaultctl show-settings
Base configuration (/etc/memfaultd.conf):
{ ... }

Runtime configuration:
{ }

Device configuration from memfault-device-info:

GIT COMMIT=unknown

Features enabled:


Immediately process memfaultd queue.

memfaultd stores events in a queue and only processes it at a fixed interval (by default 1 hour - see upload_interval_seconds). Use memfaultctl sync to force memfaultd to immediately send all events to Memfault.


This command will force an immediate coredump which will be captured by memfaultd and immediately uploaded to Memfault. Use this command to verify that the Memfault SDK is configured properly and that your symbols have been uploaded.


$ memfaultctl trigger-coredump


Use this command to create or update device attributes. You can provide multiple attributes in one call.

# memfaultctl write-attributes APP_VERSION=1.4.2 ACTIVATED=true

Attributes uploaded with this command can only be used as device attributes and not as time series metrics in Memfault. Refer to our metrics guide to upload application-specific

The Memfault SDK does not attempt to avoid unnecessary calls. Every call to this command will eventually trigger a network request. You should avoid setting the same value repeatedly as this would increase network usage.

Attribute types

memfaultctl will try to guess the type of the attributes:

  • true/false are converted to boolean values;
  • Numbers are converted to float values;
  • Anything else is uploaded as a string.

To force memfaultctl to treat the value as a string, you can enclose the value with double-quote. You will typically need to escape the double quotes so they are not removed by the shell:

# memfaultctl write-attributes APP_VERSION=\\"1.4\\"


In developer mode, attributes are flushed immediately to Memfault. Otherwise, they are stored in the queue and processed with other events.

Use memfaultctl sync to force an immediate synchronization of the attributes.