Postfix Cyrus Web cyradm HOWTO

messages are indexed to improve Cyrus performance, specially with lots of users

and/or lots of big emails. There is nothing else as fast as the Cyrus IMAP server.

Another very important feature is that you don't need a local Un*x user for each

account. All users are authenticated by the IMAP Server. This makes it a great

solution when you have a really huge number of users.

User administration is done by special IMAP commands. This allows you to either

use the commandline interface or use one of the available Web interfaces. This

method is much more secure than a Webinterface to

/etc/passwd

.

Starting from Cyrus 2.1, SASL lib version 2 is used for authentication. For the

setup described in this HOWTO, a tree layer authentication is implemented. Cyrus

authenticates with saslauthdaemon which forwards the request to pam_mysql which

finally looks up the user information in the MySQL table.

Since CMU changed the license policy for Cyrus, this software is going to be used

by many more users.

2.3. Cyrus SASL

SASL means  Simple Authentication and Security Layer . It is standardized by the

IETF (Internet Engineering Taskforce). SASL is used by network servers (in this

case Cyrus IMAP) to handle authentication requests from clients.

Cyrus SASL is a extensive software, and sometimes not easy to understand. Even I

have just the minimum knowledge needed to write this HOWTO.

2.4. OpenSSL

OpenSSL is a library needed by SASL for encryption of the data stream. It is used

by almost all opensource software that need encryption. Most or all Un*x

distributions come with a pre installed OpenSSL. Be sure to also install the

appropriate devel package. If you like, you can compile OpenSSL by yourself. This

will be required if you need to fix a security hole.

2.5. MySQL Database

MySQL is a very fast, powerful and very easy to use database.

Since Cyrus can authenticate its users with pam, you can use pam_mysql as a

connector to the user database stored in MySQL. This allows you to create a nice

Webinterface for your users for changing passwords, defining and deleting aliases

and more.

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