Users and groups

We've covered users and groups in terms of file permissions, but it's a good idea to run over what we know about users and groups in brief.

In this section, we're going to delve into a short primer on users and groups, determining which user a process is running as, how it changes to that user, and finding which users exist on your system by using /etc/passwd and similar commands.

Getting ready

Use Vagrant to connect to your Ubuntu and CentOS VMs, in different windows or one after the other:

$ vagrant ssh centos7
$ vagrant ssh ubuntu1804

How to do it...

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