Installer creates multiple users in OS each time it is executed

Behavior

When installing Confluence using the installer on Linux OS, it creates a new user in the system to run Confluence with. Each time the installer is executed on the same OS, a new user is created. Upgrading Confluence with the installer also produced the same behavior.

Based on tests, Confluence created multiple Confluence users with the same name on the same OS. Depending on OS settings, we may see Confluence creating users and appending a number in front to differentiate them. EG: confluence, confluence1, confluence2, etc...

Environment tested

• Confluence 6.15.3
• Ubuntu 18.04.1

Recommended changes to installer process

Confluence installer should ask if you want to create a new user or use the existing Confluence user in Linux OS when installing/upgrading Confluence.