You can use pre-seeding for this, using the debconf-set-selections command to pre-answer the questions asked by debconf before installing the package. For example: debconf-set-selections <<< “postfix postfix/mailname string your.hostname.com” debconf-set-selections <<< “postfix postfix/main_mailer_type string ‘Internet Site'” apt-get install –assume-yes postfix
Port 25 needs to be open in order for it to receive mail from the internet. All mail servers will establish a connection on port 25 and initiate TLS (encryption) on that port if necessary. Secure SMTP (port 465) is used only by clients connecting to your server in order to send mail out. Port … Read more
According to postqueue(1) you can simply run postqueue -f to flush your mail queue. If the mails aren’t delivered after flushing the queue but are being requeued instead, you might want to check your mail logs for errors. Taking a peek at postsuper(1) might also be helpful. Maybe the messages are on hold and need … Read more