What linux user accounts should be created prior to Drupal 7 install? When preparing to install Drupal 7 on a clean linux installation (Centos 7 in my situation), what linux user accounts should be created?

I ask this question because I seem to be having problems with file permissions or ownership when installing new modules with Drush.  When I do so I get an error like the following:

... /sites/all/modules exists, but is not writable. Please check directory permissions.

I only have 2 linux accounts on this system, root and myself, and typically run Drush as myself rather than root.  I have run 'Drush fp' to fix file permission problems, but this error persists.

So what linux accounts besides root should be created for use with Drupal and what should the user file permissions be?  Thanks
With your own user is enough.

If you want know how setup permissions check securing file permissions drupal community doc. It's referenced in this related issue.

In that specific case (setting up permissions for modules folder), it says the following:


  drwxr-x--- 32 greg-user   www-data    4096 2008-01-18 11:48 modules/


Now docs examples are for D8 but it works for D7 too.