/terraform-local-mta-exim.tf

Exim MTA configuration (no submission)

Primary LanguageHCLMIT LicenseMIT

Exim Mail Transfer Agent

This module will set up on the host running it a mail transfer agent (MTA) using the Exim software. It will only function as a MTA and in particular will not handle mail submission (authenticated or local), DKIM signing, local delivery. This is enforced to ensure the most strict security and to run the MTA with the least priviledges.

Features include:

  • Running only on port 25
  • STARTTLS with externally provided certificates
  • Only accepting e-mails for one of the local or relayed domains
  • accept deliveries using SMTP or LMTP

Requirements

  • terraform-provider-sys needs to be manually installed until i split this provider into better suited providers.
  • force-bind needs to be installed separately in /usr/local/bin/force-bind
  • Debian host as several specificities are hardcoded until portability is implemented.
  • certificates for fqdn installed in standard let's encrypt location

Configuration

fqdn

The fully qualified domain name to advertise on HELO. Will be a local delivery domain.

local_domains

Hash map containins as keys the local domains to be delivered locally as as value the delivery method. Valid delivery methods are:

  • lmtp:/path/to/unix.sock: the path must contain at least one / to be detected as a unix socket.

  • lmtp:hostname:port: deliver using LMTP over TCP with hiven hostname and port

relay_domains

List of domains to relay

sd_prefix

Systemd prefix to include before the systemd unit names.