Bitrix24 Self-hosted administration

Module settings are configured at the path Settings > System Settings > Module Settings > Mail. The settings are not complicated and most field names are self-explanatory.

When BitrixVA Learn more about Bitrix Virtual Appliance , Virtual Appliance is not employed, the Mail module settings must contain a command line for running PHP-script.

There are several system limits:

• Server must not contain applications that "listen in" the same URL and port.
• In Linux, the port 25 (or, more precisely, 1-1024) can be listened by applications, launched from root user, which is not always possible. That's why, this limit must be overcomed using the setting such as authbind. The command line will look as follows: authbind php -c /etc/php.ini. Sometimes, it's more convenient to configure forwarding at the firewall config (use port 20225 to run the server, and forward from external port 25 to internal port 20225.
• For external mail servers to reach your server, you need to open this port inside the firewall settings.
• Domains, selected in the mailbox settings, must have DNS record "MX" MX record (mail exchanger) — DNS record type, designed for email routing using the SMTP protocol.
  
  Learn more... (or "A") for IP-address, "listened" by SMTP SMTP (Simple Mail Transfer Protocol) — is a widespread network protocol, designed for email forwarding in TCP/IP networks.
  
  Learn more... -server. Usually, server that replies using the specified domain using the protocol http, contains SMTP, enabled at the same URL. In this case, no more settings are required.

When the platform and the environment are configured correctly, clicking at Run SMTP Server launches PHP script that will listen the indicated port at the specified hosts. And in case of inbound connections, it will receive incoming messages using the mail module filtering rules, sorting and processing them as well.