Forum OpenACS Q&A: Re: Post installation: configure oacs-5-9 nsd to autostart and postfix configured to send notifications
One of the features of using install-ns is that nsd should autostart anytime after 'start oacs-5-9' has been issued. The feature turns off after 'stop oacs-5-9' has been issued.
OpenACS usually "just works" if the local mail system is working.
Getting email to work on a localhost may be tricky as it likely depends at least partly on your local ISP; unless the email server is working in isolation with the localhost system. Here's a link for ubuntu: https://help.ubuntu.com/lts/serverguide/postfix.html