- Plesk Onyx for Linux
Docker service is still running on the server, while Docker component was removed from Plesk via Tools & Settings > Updates and Upgrades or Plesk installer.
This is expected behavior.
Docker is not being removed from the server upon the component removal from Plesk, since the Docker itself may be used independently of Plesk, and services and websites may rely on it.
Therefore, upon component removal, only integration between Plesk and Docker is being removed, while the Docker itself remains intact.
This unclear behavior is known as a Plesk bug #PPPM-5422 and it will be addressed in future product updates.
If Docker is needed to be completely removed, connect to the server via SSH and remove corresponding packages manually.
# yum remove docker-engine docker-engine-selinux libseccomp -y
# apt-get remove docker-* -y