I'm about to upgrade my postgresql to the latest 9.3 version

 

On my test server eveything works.

However I want to save a backup of my production server before the upgrade...

I'm not sure how I do that.

 

It says that only system files are changed during upgrade... which folders exactly I need to save on the side for roll back?

I know I can take a snap shoot of my server before the update but i'm affried that rolling back to this snap shoot will also roll back the data itself?

Since after the update the users continue to work I don't want to lose thier data.

 

How do I do that?