Using Mender for OTA updates

Once again, we will be using the Mender client on the device, but this time operating it in managed mode, and in addition, we will be configuring a server to deploy the update so that no local interaction is needed. Mender provides an open source server for this. For documentation on how to set up this demo server, see https://docs.mender.io/2.4/getting-started/on-premise-installation.

The installation requires Docker Engine version 19.03 or later to be installed. Refer to the Docker website at https://docs.docker.com/engine/installation. It also requires Docker Compose version 1.25 or later as described here: https://docs.docker.com/compose/install/.

To verify which versions of Docker and Docker Compose you have on your system, use these commands:

$ docker --version
Docker version 19.03.8, build afacb8b7f0
$ docker-compose --version
docker-compose version 1.25.0, build unknown

The Mender server also requires a command-line JSON parser called...