describe installing Postfix as Mailrelay

README.md

@@ -58,6 +58,7 @@ enable EPEL Repo:
 # firewall-cmd --add-service={http,https} --permanent
 # firewall-cmd --remove-service=cockpit --permanent
 # firewall-cmd --add-port=1883/tcp --permanent   ; only for MQTT
+# firewall-cmd --add-port=25/tcp --permanent     ; for Postfix
 # firewall-cmd --reload
 
 List Rules:
@@ -303,7 +304,33 @@ containers$ systemctl --user start podman-kube@$escaped.service
 containers$ systemctl --user enable podman-kube@$escaped.service
 ```
 
+## Postfix
 
+```bash
+# dnf install postfix
+
+/etc/postfix/main.cf:
+---
+inet_interfaces = all
+
+virtual_alias_domains = wo-bisch.ch mini-beieli.ch
+virtual_alias_maps = hash:/etc/postfix/virtual
+---
+
+# tail -2 /etc/postfix/virtual
+info@mini-beieli.ch info@nbit.ch
+info@wo-bisch.ch info@nbit.ch
+
+# postmap /etc/postfix/virtual
+
+# systemctl enable postfix
+# systemctl start postfix
+
+Creat DNS Records:
+mx1.nbit.ch and mx2.nbit.ch (A/AAAA Records to the same IPs as onyx and onyx-dev)
+
+Change SPF Records to include mx1 and mx2
+```
 
 ## Secondary Nameserver