The goal of this project, to some extent, has been to create an environment that functions similarly to a Microsoft exchange +OWA environment using only open-source programs and in a linux environment. The solution had to be robust and scalable and similar to what a small to medium business would use. For the most part I’ve achieved that, however I’ll admit that at this point the lack of a backup solution is a concern. But we’ll put that aside for the time being (due to financial constraints).

I would expect that most end users would be able to adopt the software quickly and integrate it into their workflows. My project would cover most of the basic functions of an office environment, however clearly does not aim to replace or integrate with other software such as HP TRIM, Docushare, Objective etc. Furthermore as far as I’m aware my environment would not be able to support the integration of those programs into the mail server. I digress.

To recap: I’ve been able to create a postfix/dovecot IMAP mail server, secured with SSL. The web interface allows password on the MYSQL backend to be reset by the user. Shared calendar functions are supported by Own Cloud which also supports file sharing and limited online editing of documents. Again, all secured by true SSL thanks to let’s encrypt.

The backend also has web hosting capabilities and useful user management and administration functions. PhpMyAdmin (locked down to the local subnet), PostFixAdmin, the aforementioned Own Cloud are all installed and offer reasonable admin functions similar to to an exchange/AD environment. Any L1 technician would be able to use the backends without too much hassle.

So the final stage will be to setup two more things.

1. Mailman or similar: PostFixAdmin handles mail aliases well (I would say they’re easier to create than Office365 with ADFS integration) however distribution groups are not supported.
2. Setting up apache on the web server to handle all incoming requests to the mail server by using the proxy modules. The picture below should demonstrate:

Fundamentally, the web server will encrypt all the incoming traffic or push clients to SSL connections. It will map the following from the mail server:

• http://mail.warbel.net/owncloud to https://www.warbel.net/owncloud
• http://mail.warbel.net/roundcube to https://www.warbel.net/roundcube
• http://mail.warbel.net/postfixadmin to https://www.warbel.net/postfixadmin

The traffice between the mail server and the www server will technically be unencrypted. Given that they’re both VMs running on the same host though, this presents a limited security hole. The mail server will also be configured to firewall off all incoming connections on port 80 and 443 that are not coming from the web server.