openbsd-mailserver

Setup mail server using ansible, based on the wonderful guide by TuM'Fatig (Joel Carnat) https://www.tumfatig.net/2023/self-hosted-email-services-on-openbsd/

Requirements

Ansible >= 2.7
Server with OpenBSD (tested working as of OpenBSD 7.4)
SSH key to login to the server
Public domain resolving to the server (MX, AAAA and A)

Configuration

Dovecot
OpenSMTPD
RspamD
acme-client
httpd

Setup your DNS!

A       @       123.123.123.123

AAAA    @       0000:0000:0000:000:00

A       mail    123.123.123.123

AAAA    mail       0000:0000:0000:000:00

A       mta-sts    123.123.123.123

AAAA    mta-sts       0000:0000:0000:000:00

MX      @       mail.example.com

SPF domain rules

TXT     @       v=spf1 mx:example.com -all ~all

DMARC domain policy

TXT     _dmarc       v=DMARC1; p=reject; adkim=s; aspf=s;

MTA-STS and TLSRPT policies

You can use the current date as the mta-sts ID

TXT     _mta-sts        v=STSv1; id=20190811231231

Make sure to edit the reporting address to a address you control

TXT     _smtp._tls      v=TLSRPTv1; rua=mailto:[email protected]

Inventory

Set the hostname in the inventory file hosts

Variables

All variables are stored in the vars file. Set the values according to your server.

Run the playbook

ansible-playbook install.yml

Set your DKIM DNS

The playbook will generate the DKIM DNS, check this file for what to enter in your DNS

/etc/mail/dkim-dns-example.txt

Don't skip this step unless you want to go to the spam folder.

Setup DANE email security

Make sure to enable DNSSEC at your domain provider!

Now you need to create a TLSA record, you can use this tool to generate one:

https://www.huque.com/bin/gen_tlsa

Use the public key from your domain to generate the TLSA record.

Usage field: DANE-EE
Selector field: SPKI
Matching type field: SHA-256: SHA-256 hash
Port: 25
Transport protocol: tcp
Domain name: (your mail server fqdn)

Check rspamd reporting

You can use the rspamd web GUI to view spam:

# ssh -L 11334:localhost:11334 <mail server>

Browse to http://localhost:11334/

Contributions

Contributions welcome

Credits

Check out these articles and tutorials that I used to create this Ansible-Playbook

jordan-warne / openbsd-mailserver-ansible Goto Github PK