auth.conf

SMTP authentication can be configured in auth.conf. Each line has the format “user|smarthost:password”.

dma.conf

Most of the behaviour of dma can be configured in dma.conf.

SMARTHOST (string, default=mail.example.com)

If you want to send outgoing mails via a smarthost, set this variable to your smarthosts address.

PORT (numeric, default=25)

Use this port to deliver remote emails. Only useful together with the ‘SMARTHOST’ option, because dma will deliver all mails to this port, regardless of whether a smarthost is set or not.

ALIASES (string, default=/etc/aliases)

Path to the local aliases file. Just stick with the default. The aliases file is of the format

nam: dest1 dest2 ...

In this case, mails to nam will instead be delivered to dest1 and dest2, which in turn could be entries in /etc/aliases. The special name ‘*’ can be used to create a catch-all alias, which gets used if no other matching alias is found. Use the catch-all alias only if you don't want any local mail to be delivered.

SPOOLDIR (string, default=/var/spool/dma)

Path to dma's spool directory. Just stick with the default.

AUTHPATH (string, default=not set)

Path to the ‘auth.conf’ file.

SECURETRANS (boolean, default=commented)

Uncomment if you want TLS/SSL secured transfer.

STARTTLS (boolean, default=commented)

Uncomment if you want to use STARTTLS. Only useful together with ‘SECURETRANS’.

FINGERPRINT Pin the server certificate by specifying its SHA256 fingerprint. Only makes sense if you use a smarthost.

 

OPPORTUNISTIC_TLS (boolean, default=commented)

Uncomment if you want to allow the STARTTLS negotiation to fail. Most useful when dma is used without a smarthost, delivering remote messages directly to the outside mail exchangers; in opportunistic TLS mode, the connection will be encrypted if the remote server supports STARTTLS, but an unencrypted delivery will still be made if the negotiation fails. Only useful together with ‘SECURETRANS’ and ‘STARTTLS’.

CERTFILE (string, default=empty)

Path to your SSL certificate file.

SECURE (boolean, default=commented)

Uncomment this entry and change it to ‘INSECURE’ to use plain text SMTP login over an insecure connection. You have to rename this variable manually to prevent that you send your password accidentally over an insecure connection.

DEFER (boolean, default=commented)

Uncomment if you want that dma defers your mail. You have to flush your mail queue manually with the -q option. This option is handy if you are behind a dialup line.

FULLBOUNCE (boolean, default=commented)

Uncomment if you want the bounce message to include the complete original message, not just the headers.

MAILNAME (string, default=empty)

The internet hostname dma uses to identify the host. If not set or empty, the result of gethostname(3) is used. If ‘MAILNAME’ is an absolute path to a file, the first line of this file will be used as the hostname.

MASQUERADE (string, default=empty)

Masquerade the envelope-from addresses with this address/hostname. Use this setting if mails are not accepted by destination mail servers because your sender domain is invalid. This setting overrides the -f flag and the EMAIL environment variable.

If ‘MASQUERADE’ does not contain a @ sign, the string is interpreted as a host name. For example, setting ‘MASQUERADE’ to ‘john@’ on host ‘hamlet’ will send all mails as ‘john@hamlet’; setting it to ‘percolator’ will send all mails as ‘Sm off username @percolator’.

NULLCLIENT

Bypass aliases and local delivery, and instead forward all mails to the defined ‘SMARTHOST’. ‘NULLCLIENT’ requires ‘SMARTHOST’ to be set.

Environment variables

The behavior of dma can be influenced by some environment variables.

EMAIL

Used to set the sender address (envelope-from). Use a plain address, in the form of user@example.com. This value will be overridden when the ‘MASQUERADE’ config file setting or the -f flag is used.