Mail server

Mail server

sarka's picture

Last week we managed to migrate all email addresses. It was not an easy step and we manage to make one foul which complicated the work of IMAP users. Now everything is alright so let's recap. The old mail server was built on Gentoo and ran on the now insufficient hardware. In addition, did not include some important updates, which could lead to security problems. We therefore decided to put a new server based on Debian and use other software. From the new server, we have therefore promised the following: 

  • Stability and trouble-free Debian
  • The scalability
  • Deploying our virtualization technology
  • Requires less hardware
  • Resolving problems with certificates

On the new server  Debian replaced Gentoo mainly because it takes up a lot of time to keep it updated. The POP and IMAP daemon Courier cared, but which caused occasional server performance issues, so away with it. It was replaced by Dovecot, which also brings the promise of advanced filtering user adjustable (redirect, divided into folders in webmail, etc.). Virtualization currently dominates, and because we are very well prepared, we built a new mail server on a virtual server running on Dell M1000e Blade Server. This should help in the distribution of e-mail accounts on multiple servers. A new certificate should give users a sense of security to unsecured channels. The change affected users also negatively. Some began to mail via IMAP to download again, others have created a second physical box due to incorrect entries in the database that the courier work as they should. But we finally managed to solve all the problems. Unfortunately, two days later he got into trouble the database server, which is two days after migration paused and gave the necessary mail server documentation. It was a problem that was independent of the migration and now everything is fine. User waits just one unpleasant thing and change the certificate, you will be informed about that in another article. With news and some related configuration changes. We have tried to maintain compatibility previous setting  with current. More or less succeeded with certain versions of the Outlook client for which it was necessary to add a crutch. Correctly, you should have an e-mail client is configured as follows:

POP server
IMAP server
SMTP server (port 25 a 2525)

Your current settings will work. But for secure SSL / TLS communications it is recommended to set the value. If you care about your DNS yourself, you have pointed your MX record to The other equally significant change occurred in webmail, where we have updated your favorite RoundCube from version 0.3.1 to the latest stable version 0.7.2. Link to all features of the new webmail here.