Hello again my fellow Zentyal plumbers. This post is very related with the first one, this time covering Zarafa and related subsystems.


Zarafa is a groupware suite, including mail, calendars, contacts, task and notes which offers fully-fledged collaboration, sharing and access permission mechanisms. A remarkable feature of Zarafa is its integration with Microsoft clients and mobile synchronization protocols.

Let’s jump to the plumbing diagram already:

(click to enlarge image)

First of all, this diagram is a simplified and Zentyal-contextualized version of some parts of the Zarafa documentation: Zarafa Architecture, Zarafa Components. We encourage you to visit the official Zarafa documentation to continue learning about this platform.

Point by point:

A: Most of the mail subsystem components explained in the first post Plumbing part I are exactly the same for this version, so you still have Postfix as your MTA and the optional parts like Amavis security suite, Postgrey, Fetchmail and so on. Zarafa replaces the MDA, and adds the groupware services and gateways for several protocols and platforms.

B: The zarafa-dagent is the equivalent of a MDA (performing some of the roles of Dovecot for the former blogpost), it uses LMTP, a simplified and local-only version of the SMTP protocol to communicate with the MTA. Take into account that different MDA means different mailboxes for your users, if you migrate your virtual mail domain from Dovecot to Zarafa, the user mail addresses may remain the same, but they are accessing a different Inbox in different storage backend.

C: MySQL database, related to the last point. Zarafa stores mail and some mail metadata in a proper database, as opposed to the file-system based mail storage present in traditional mail systems.

D: The zarafa-spooler sends the mail waiting in the outgoing queue through the MTA.

E: Zarafa is tightly integrated with the Apache server in Zentyal, so the ‘Web Server’ module is required to offer all the web-based interfaces and protocols available to the users.

F: ‘Web access’ and ‘Web app’ are two web interfaces that offer the user a very convenient and fully featured way to access the mail and groupware services by just using their web browser. ‘Web access’ is oriented to look and feel like a microsoft outlook interface, while ‘Web app’ uses modern web protocols to improve the experience and can even integrate with chat and voice IP subsystems.

G: Z-push, an implementation of Microsoft’s ActiveSync protocol, available in all the major smartphone operative systems. Using this gateway you can synchronize all your mail, contacts and calendars information in your phone, bidirectionally, without installing additional apps and over the air.

H: Zarafa gateway for common mail services, IMAP4(S) and POP3(S), take into account that if your plan to offer a mail gateway, IMAPS for example, first you have to make sure that this port is disabled in Dovecot.

I: Microsoft Oulook offers MAPI, an interface to perform the synchronization against third party software. The Zarafa Windows Client needs to be installed in the Desktop OS. It bridges the Zarafa groupware protocols and Microsoft Outlook clients in transparent way for the users.

J: The MAPI commands are encoded in web-service SOAP and synchronized against Zarafa server.

Hope you have now a clearer vision of all the features and possibilities that Zarafa brings to the table. An important piece is missing in the diagram: how Zarafa server and Postfix connect to the LDAP to retrieve user auth and directory information. In the next post I intend to cover the Samba and Kerberos subsystems.

A post by Mateo Burillo