How do I disable NetworkManager in favor of dhcp setup?

[Micha]

I have a redhat 6 desktop based system that exhibits a behavior where
sshd fails to start on startup despite being enabled and requires manual
startup after user login. I want to enable remote access before there is
actual user login on the system

I believe I pinpointed the problem tp NetworkManager being installed and
enabled, which means that no network connection is actually configured
before a user is logged in.

I want to know how to remove NetworkManager and enable automatic network
connection startup before sshd is started.

/etc/network/interfaces doesn't exist, so I'm not sure how this is
supposed to be achieved these days (under debian it's still there, just
not active by default). It used to be possible to define the interface
as auto dhcp in there to get the behavior I want. Will just adding that
file do the trick is it supposed to be done differently?

Thanks