FeltPost E-mail Services

The Feltpost Mail Services is a Linux-based e-mail hosting solution based on Postfix, Dovecot, Modoboa and RSPAMD running on Kubernetes. All endpoints are protected by TLS encryption and periodically evaluated against services like sikkerpånettet.dk and CheckTLS.



DomainKeys Identified Mail (DKIM) is used to sign e-mail headers to ensure authenticity. If you enable DKIM for your domain, a private/public key set will be generated, and the public key will automatically be propagated to your DNS zone. If you choose to enable DKIM, please select a key length of 2048 bits.


Sieve is a system for server side filtering and filing of mail based on message headers. You can configure this through Webmail (look under Settings » Filters).

Spam Filtering

RSPAMD is used for spam identification and filtering. The system is based on Bayesian filtering, which requires only occasional manual intervention. If spam accidentally ends up in your inbox, you can retrain the filters by moving it to your Spam folder. If legitimate e-mail ends up in your Spam folder, you retrain the filters by moving it out of that folder.

As the filter training is a collaborative effort, you will help improve the experience for everyone by training the filters correctly. That means only actual spam should be moved to the Spam folder, and unwanted - but otherwise legitimate messages - should go in the Trash folder. Newsletters you actually signed up for, is not spam.

The Spam folder is a special use folder, which means it may be represented differently across different clients, but it always serve the same purpose. Thunderbird calls it Junk and the Gmail app for Android calls it Spam.

Client Configuration

Incoming (IMAP)

Server Name: imap.feltpost.com
Port: 993
User Name: you@yourdomain.com
Connection Security: SSL/TLS
Authentication Method: Normal password

Outgoing (SMTP)

Server Name: smtp.feltpost.com
Port: 465
User Name: you@yourdomain.com
Connection Security: SSL/TLS
Authentication Method: Normal password


Delivery Issues

If you're having delivery issues, there could be a number of reasons.

Try running through this checklist: