I’m continuing to play with a new NethServer 6.8 installation, and I’m trying to figure out if/how NethServer can be configured to send email to external email addresses. From the NethServer documentation (http://docs.nethserver.org/en/latest/mail.html):
NethServer can handle an unlimited number of mail domains, configurable from the Email
Domains page. For each domain there are two alternatives:
Deliver messages to local mailboxes, according to the Maildir  format.
Relay messages to another mail server.
So am I correct in saying that NethServer isn’t meant to be used to send email to external email addresses? I see that you can relay email to an external mail server, but what about just using Postfix already installed with NethServer?
A little background for why I want to do this: I’m in the middle of installing Mail Piler on my NethServer box, and it appears I need an SMTP server in order to forward archived emails to users. The idea is that a user can “restore” an email that has been archiving in Mail Piler. This “restore” function just forwards the email to the user. My plan was to use Postfix to send the email to the user since my production mail server is on VPS elsewhere (MailEnable v9.0.x on MS Server 2012).
Any assistance would be greatly appreciated. I’m a Linux noob and I don’t have much experience with mail servers in general. Thanks for everyone’s assistance and patience!