Ubuntu Linux: How do I list all of the services on my Ubuntu 18.04 or Ubuntu 20.04 system from the Linux command line / Terminal ?  How to list running services on Linux / Ubuntu 20.04 ?

Answer: Use this command:

service --status-all

Here’s an example of what this looks like on an Ubuntu 18.04 LTS system:

The meaning of the Ubuntu service command output

From the Ubuntu Linux service man page:

service --status-all runs all init scripts, in alphabetical order, with the status command. The status is:

• [ + ] running services
• [ - ] stopped services
• [ ? ] services without a ‘status’ command

This option only calls status for sysvinit jobs; upstart jobs can be queried in a similar manner with initctl list.

How to show the Ubuntu version

In a slightly-related note, you can show your Ubuntu version information with the lsb_release -a command:

root> lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description:    Ubuntu 18.04.2 LTS
Release:    18.04
Codename:   bionic