Dreamhost VPS Debian Sudoers File

Hi, I can’t find Sudoers file in debian VPS.

I tried to install. apt-get install sudo. but it won’t let me.

Please guide me.

I need to run command from PHP which shouldn’t prompt password.

Here is example what I am trying to do.

add this line at the end of /etc/sudoers:
www-data ALL= NOPASSWD: /usr/sbin/ejabberdctl