---
name: "mta-sts-daemon"
section: "1"
platform: "linux"
package: "postfix-mta-sts-resolver"
version: "1.5.0-1"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/mta-sts-daemon"
---

# mta-sts-daemon(1)

provide MTA-STS policy to Postfix as policy map

## NAME

mta-sts-daemon - provide MTA-STS policy to Postfix as policy map

## SYNOPSIS

**mta-sts-daemon** \[*OPTION*\]...

## DESCRIPTION

This daemon opens a socket where Postfix can query and retrieve the MTA-STS policy for a domain.  The configuration file is described in [**mta-sts-daemon.yml**(5)](/mta-sts-daemon.yml/5.md).

MTA-STS, specified in RFC 8461 \[0\], is a security standard for email servers. When a site configures MTA-STS, other mail servers can require the successful authentication of that site when forwarding mail there.

## OPTIONS

- **-h, --help**

  show a help message and exit

- **-v, --verbosity** *VERBOSITY*

  set log verbosity level: *debug*, *info* (default), *warn*, *error*, or *fatal*.

- **-c, --config** *FILE*

  config file location (default: */etc/mta-sts-daemon.yml*)

- **-g, --group** *GROUP*

  change eGID to this group (default: *none*)

- **-l, --logfile** *FILE*

  log file location (default: *none*)

- **-p, --pidfile** *PIDFILE*

  name of the file to write the current pid to (default: *none*)

- **-u, --user** *USER*

  change eUID to this user (default: *none*)

- **--disable-uvloop**

  do not use uvloop even if it is available (default: enabled if available)

## EXAMPLES

Configure Postfix in */etc/postfix/main.cf*:

```
smtp_tls_policy_maps = socketmap:inet:127.0.0.1:8461:postfix
smtp_tls_CApath = /etc/ssl/certs/
```

Reload Postfix.  Then verify it works:

**/usr/sbin/postmap -q dismail.de socketmap:inet:127.0.0.1:8461:postfix**

This configuration overrides DANE TLS authentication. If you wish to meet the requirement of RFC 8461, section 2, you should list a DANE policy resolver (or a static lookup table for domains known to implement both MTA-STS & DANE) before mta-sts-daemon in smtp\_tls\_policy\_maps.

## SEE ALSO

[**mta-sts-query**(1)](/mta-sts-query/1.md), [**mta-sts-daemon.yml**(5)](/mta-sts-daemon.yml/5.md)

## NOTES

0\.

**SMTP MTA Strict Transport Security (MTA-STS)**:  \<https://tools.ietf.org/html/rfc8461\>