Hi Juan,
Since you already ran the install-ns scripts[1], another method of controlling the server should already be installed.
What results do you get from typing:
status 5-9
If result is '5-9 start/running, process <some number>' then nsd is already running.
If result is 'status: Unknown job: 5-9' then nsd might not be installed, or has another service name provided by the install-ns.sh and install-oacs.sh scripts.
If result is '5-9 stop/waiting', then openacs can be started with:
sudo start 5-9
1. https://openacs.org/forums/message-view?message_id=5366908