Editing daemon.json *nvm, using postfix

[99isfailure]

I'm attempting to install mailcow on my SO VM to send alerts if/when triggered. I'm currently stuck at the step to modify the /etc/docker/daemon.json file and add the "selinux-enabled : true" line. I should be getting a return when running "docker info | grep selinux" after updating the file but I am not. Also, when I restart the machine the daemon.json file goes back to the default configuration. Any help would be appreciated.

[weslambert]

Can you let me know why you need to enable selinux-enabled: true? What kind of alerts/mail are you looking to receive?

[99isfailure]

It's from a tutorial I was following https://mailcow.github.io/mailcow-dockerized-docs/i_u_m_install/
My end-goal is to receive alerts from Security Onion when a certain risk level is triggered (ex. emailed when there's a critical alert).