tutorials/nullmailer.md

+The easiest way to set up a forwarding mail server on a host is to use the package nullmailer.
+
+# configuration
+
+To configure it, you have to create some files:
+
+## adminaddr
+
+This file contains the address of the admin user that should be contacted in case of problems. The file is located in `/etc/nullmailer/adminaddr`:
+
+```
+address@example.com
+```
+
+## defaultdomain
+
+This file contains the domain of the local network. The file is also located in `/etc/nullmailer`:
+
+```
+host.example.com
+```
+
+## me
+
+This files contains the name of the host in the LAN.
+
+```
+host.fritz.box
+```
+
+## remotes
+
+This file configures, where to connect to to send the emails. Choose one of the configurations.
+
+```
+# Format is: HOST PROTOCOL [OPTIONS]
+# HOST = IP or DNS
+# PROTOCOL = smtp | qmtp
+# OPTIONS = [port=NUMBER] [user] [pass] [starttls | ssl [insecure] ]
+#
+# Examples:
+# A standard SMTP server:
+# somesendmailserver.domain.com smtp
+#
+# A qmail server with QMQP setup:
+# someqmailserver.domain.com qmqp
+#
+# A nonstandard SMTP server setup:
+# someotherserver.domain.com smtp port=2525
+#
+# SMTP server supporting AUTH PLAIN
+# mailserver smtp user=<user> pass=<pass>
+#
+# SMTP server supporting AUTH LOGIN 
+# mailserver smtp user=<user> pass=<pass> auth-login
+#
+# SMTP server with smtps (legacy - use starttls instead)
+# mailserver smtp user=<user> pass=<pass> port=465 ssl
+#
+# SMTP server on submission port with starttls
+# mailserver smtp user=<user> pass=<pass> port=587 starttls
+#
+# SMTP server on submission port with starttls and self-signed certificate
+# mailserver smtp user=<user> pass=<pass> port=587 starttls insecure
+#
+# mail.example.com smtp port=587 starttls
+```
+
+All mails are now sent through the configured mailserver.
+
+## allmailfrom
+
+If you specify an email address in this file, then all mails have this address as sender.
+
+```
+from@example.com
+```
+
+# Further documentation
+
+http://www.troubleshooters.com/linux/nullmailer/