Fully featured mail server with DBMail

DBMail is an essential part of a fully featured mail server, it has many loosely connected parts including email, address books, calendar, mailing lists, reporting and cybersecurity threat identification and prevention. This page shows the breath of services and why they are involved.

Users almost always only come into contact and use a Message User Agent such as Outlook, Thunderbird, KMail or webmail to manage their emails. Behind the scenes there are a number of integrated services that ensure they never need to know how it works and they can effortlessly and reliably carry out their daily tasks from any of their devices.

Authentication

DBMail has it's own SQL authentication or can integrate with your organisations single sign-on using LDAP or Active Directory. Responsibility is to ensure only authorised users get access to their information.

Mail Transfer Agent

Organisations need to send and receive emails and the service for that is a Message Transfer Agent (MTA), it's responsible for receiving and forwarding emails.

There are many MTAs, with sendmail one of the earliest. The one chosen at Persistent Objects is Exim as it's highly configurable with extensive facilities, its configuration is straightforward, is open source and available for almost every Linux and Unix distribution.

XML Team sponsored the Exim DBMail configuration and is recommended for integrating the two.

User access to their emails

Designed in 1986, IMAP is the current standard for users to manage their email, it's available on almost every device from mobiles to desktops and is also used by CRM software and corporate systems to manage emails. One of the benefits of IMAP is efficiently managing emails on mobiles, desktops and webmail.

DBMail implements IMAP, Local Mail Transfer Protocol (LMTP) a message delivery agent (MDA) for receiving mail, a previous standard Post Office Protocol (POP3) and ManageSieve protocol for managing Sieve scripts to organise their incoming email.

Thanks to its database storage, DBMail has excellent replication, high performance, scalability, searching and integration with other systems.

Address books and calendars

Keeping diary, todo lists and address books online is invaluable for keeping your information wherever you go, and desktop, mobile and webmail clients conveniently integrate with CardDAV and CalDAV.

Radicale is a minimal server that can be configured to work with LDAP and SQL via Apache Authentication.

Most people have address books and calendars, by maintaining a central service based on industry standards CalDAV and CardDAV users can keep the same lists on their mobiles and desktops.

Free and Open-Source CalDAV and CardDAV Server

Mailing list service

Mailing lists are invaluable for managing subscriptions. Even the simplest of lists benefit from automating common tasks subscribing and unsubscribing users, showing archives and preventing abuse.

Unlike hosted lists, you have full control.

I've been using Sympa since 1999 and a minor patch of mine was accepted in 2002.

High availability

Users rely on and expect 24x7 from their services.

Monitoring the various services and automatically restarting them when necessary is essential for low maintenance high availability services.

See Manage / High availability for more.

Analysis reports

DBMail has configurable logs and native SQL that can be analysed and reported using off the shelf analysis software.

See Manage / Activity reports for a Grafana example.

Defence

Cybersecurity is essential for any internet connected service to prevent unwanted access and provide an audit log should one occur.

See Manage/Defence for examples using Fail2Ban.