Autoconfig Worker¶

The autoconfig worker serves email client auto-configuration for every hosted domain: Mozilla Autoconfig (Thunderbird), Microsoft Autodiscover (Outlook), MTA-STS policies, and a DNS record generator. It is a FastAPI service that answers with the advertised mail hostname (MAIL_HOSTNAME) so clients are configured against the customer-facing IMAP/SMTP name, not the server's PTR identity.

Publicly Routed Since 2026-08-27¶

Client auto-setup must answer for every customer domain, not just this server's own. The production Traefik router uses HostRegexp wildcards:

HostRegexp(`autoconfig.{domain:.+}`) || HostRegexp(`autodiscover.{domain:.+}`) || HostRegexp(`mta-sts.{domain:.+}`)

Before 2026-08-27 the rule was a single literal Host('autoconfig.${DOMAIN}'), so autoconfig.<customer-domain> and every autodiscover.* host 404'd -- while the panel told customers to create exactly those DNS records. Certificates for these hostnames are issued by cert_manager.

API Endpoints¶

Copied from the route decorators in worker/autoconfig/app.py:

GET  /mail/config-v1.1.xml                          -- Mozilla Autoconfig
GET  /.well-known/autoconfig/mail/config-v1.1.xml   -- Mozilla Autoconfig (alt path)
POST /autodiscover/autodiscover.xml                 -- Microsoft Autodiscover POX
POST /autodiscover/autodiscover.json                -- Microsoft Autodiscover V2
GET  /mta-sts.txt                                   -- MTA-STS policy
GET  /.well-known/mta-sts.txt                       -- MTA-STS policy (canonical path)
GET  /dns-records/{domain}                          -- DNS record generator for a domain
GET  /health                                        -- Health check
GET  /metrics                                       -- Prometheus metrics

Configuration¶

Docker Configuration¶

autoconfig:
  build:
    context: .
    dockerfile: ./worker/autoconfig/Dockerfile
  container_name: autoconfig
  ports:
    - "8100:8100"
  depends_on:
    - mysql
    - migrate

In production the host port is bound to 127.0.0.1; all public traffic arrives through the Traefik wildcard router above.

Gotchas¶