What is dma?

dma (DragonFly Mail Agent) is a lightweight MTA for home and office environments. It accepts emails from local mail clients and delivers them locally or to remote destinations via SMTP. It supports TLS/SSL encryption and SMTP authentication for secure remote delivery. Unlike full MTAs such as sendmail or Postfix, dma does not accept incoming connections on port 25, making it suitable for outbound-only mail. It installs via package managers on FreeBSD, Ubuntu, and Arch, or builds from source on Linux and BSD. Configuration uses two files in /etc/dma: auth.conf for SMTP credentials and dma.conf for smarthost, port, aliases, spool directory, and TLS options. Licensed under a BSD-style license, actively maintained since 2011.

Should you self-host dma?

dma scores 48/100 on selfhost.directory (how scoring works) and ranks #65 of 106 in Email. It has 266 GitHub stars.

There was no stable release in the past 12 months, so check the repository's recent activity before you rely on it.

Setup is moderate: expect some configuration beyond a single command. It is Other-licensed and written mostly in C.

Its closest alternative on selfhost.directory is Listmonk (80/100, 24 017 stars). It scores higher overall, so compare the two before you pick. See dma vs Listmonk side by side.

Features

Address masquerading
Alias support
Certificate pinning
Local Mail Delivery
Mail queue management
Null client mode
Opportunistic TLS
Remote Mail Delivery
Smarthost relay
SMTP Authentication
STARTTLS support
TLS/SSL Support

How to configure dma

ALIASES/etc/aliasesPath to local aliases file
Path to local aliases file
values: string (file path)
AUTHPATHnot setPath to the auth.conf file
Path to the auth.conf file
values: string (file path)
CERTFILEemptyPath to SSL certificate file
Path to SSL certificate file
values: string (file path)
DEFERcommented (disabled)Defer mail delivery, requiring manual queue flush
Defer mail delivery, requiring manual queue flush
values: boolean (YES/NO)
FINGERPRINTemptySHA256 fingerprint of server certificate for pinning
SHA256 fingerprint of server certificate for pinning
values: string (SHA256 hex)
FULLBOUNCEcommented (disabled)Include complete original message in bounce messages
Include complete original message in bounce messages
values: boolean (YES/NO)
MAILNAMEempty (uses gethostname)Internet hostname dma uses to identify the host
Internet hostname dma uses to identify the host
values: string (hostname or file path)
MASQUERADEemptyMasquerade envelope-from addresses
Masquerade envelope-from addresses
values: string (email address or hostname)
NULLCLIENTcommented (disabled)Bypass aliases and local delivery, forward all mail to smarthost
Bypass aliases and local delivery, forward all mail to smarthost
values: boolean (YES/NO)
OPPORTUNISTIC_TLScommented (disabled)Allow STARTTLS negotiation to fail
Allow STARTTLS negotiation to fail
values: boolean (YES/NO)
PORT25Port to use for remote email delivery
Port to use for remote email delivery
values: numeric
SECUREcommented (disabled)Allow plain text SMTP login over insecure connection
Allow plain text SMTP login over insecure connection
values: boolean (YES/NO or INSECURE)
SECURETRANSFERcommented (disabled)Enable TLS/SSL secured transfer
Enable TLS/SSL secured transfer
values: boolean (YES/NO)
SMARTHOSTemptyRemote SMTP server to relay outgoing mail through
Remote SMTP server to relay outgoing mail through
values: string (hostname or IP)
SPOOLDIR/var/spool/dmaPath to dma's spool directory
Path to dma's spool directory
values: string (file path)
STARTTLScommented (disabled)Use STARTTLS for opportunistic TLS
Use STARTTLS for opportunistic TLS
values: boolean (YES/NO)