Tips and tutorials

Tips and tutorials for beginners and experts alike

    Agent Installation FAQ

    Can I limit the CPU and memory the agent uses?

    Yes, the CPU and memory that the agent uses can be limited using systemctl as follows:

    systemctl set-property formant-agent.service MemoryLimit=<value>
    systemctl set-property formant-agent.service CPUQuota=<value>

    For example, to lock the agent to using a maximum of 1 core

    systemctl set-property formant-agent.service CPUQuota=100%

    Can I download the Formant agent and sidecar Debian packages directly?

    Yes. See here for debian packages.

    Install using dpkg -i <formant-package>.deb

    Can I download the Formant agent and sidecar Debian packages directly?

    Yes. See here for debian packages.

    Install using dpkg -i <formant-package>.deb

    Can I install the Formant agent on Windows or MacOS?

    We support agent installation via docker container for non-Linux systems. See documentation on installing the agent in docker container.

    What environment variables can I add to /var/lib/formant/.bashrc?

    Here is a list of all optional environment variables that affect the behavior of the Formant agent.


    Please make sure to restart the agent (systemctl restart formant-agent) for the environment variables to take effect 

    // The IP address where the Formant Agent will start it's server

    // The Unix Socket where the Formant Agent will start it's server

    // The port where the Formant Agent will expose the gRPC interface

    // The port where the Formant Agent will expose the HTTP interface

    // Enables the local port forwarding feature

    The following environment variables are ROS-specific:

    // The path to the root of the catkin workspace. The Formant agent uses this to find custom ROS message definitions

    // If the ROS setup files are not in <catkin_ws>/devel/setup.bash, the custom location of ROS setup script

    // The file location of the Python interpreter used by the tf2 bridge

    // The file location of the Python3 interpreter used by the ROS bridge

    // The address of the ROS master to which the ROS Bridge connects

    // The file localtion of the unix socket used for the ROS bridge

    // Enables replacement of timestamps on ROS messages with the current time

    How can I make the "formant" user use a different python than the system level python?

    Export FORMANT_AGENT_PYTHON_PATH and FORMANT_AGENT_PYTHON3_PATH to the desired values in /var/lib/formant/.bashrc to specify the pythons the formant user will use. These values default to python and python3.

    How can I source a custom script before the Formant agent process starts?

    Export the SOURCE_SCRIPT environment variable in /var/lib/formant/.bashrc to the location of the custom script. The "formant" user will source the provided script before executing the Formant agent process.

    Agent setup troubleshooting

    The Formant agent ROS bridge is not running

    Most parts of the formant agent ROS bridge are python3 processes. Try running import rospy in a python3 shell. If this import errors, you may have to install python3-roskpg-modules:

    apt install python3-rospkg-modules

    Please make sure you have the following packages installed on pyhton3 for ros_bridge:


    The following packages need to be installed on python2 for tf2_bridge:


    ImportError: cannot import name Gst, introspection typelib not found

    Some systems will not have a video streaming dependency installed. To fix, you can install the following:

    apt install gir1.2-gst-rtsp-server-1.0

    /usr/sbin/policy-rc.d returned 101, not running 'enable formant-agent.service'

    The system's policy-rd.d may be set up to disallow enabling services. Edit /usr/sbin/policy-rc.d to exit 0 instead of 101.

    ROS data not showing up on webapp

    If the installation was successful, but the ROS based data is not displaying on the webapp, it is likely that the agent did not detect that it was ROS based device. Check if ROS_MASTER is set in your environment. If it is not set, then set it as follows:

    export ROS_MASTER_URI=http://localhost:11311

    Then rerun the agent installation command you ran without the token. If you ran the docker based agent installation, rerun the docker based command. 

    Still don't find what you are looking for?

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