Follow Techotopia on Twitter

On-line Guides
All Guides
eBook Store
iOS / Android
Linux for Beginners
Office Productivity
Linux Installation
Linux Security
Linux Utilities
Linux Virtualization
Linux Kernel
System/Network Admin
Scripting Languages
Development Tools
Web Development
GUI Toolkits/Desktop
Mail Systems
Eclipse Documentation

How To Guides
General System Admin
Linux Security
Linux Filesystems
Web Servers
Graphics & Desktop
PC Hardware
Problem Solutions
Privacy Policy




How to set up IMAP server Cyrus

My choice is Cyrus, that is part of the Kolab set of software, so if l will go for Kolab in the future, at least I'm acquainted with it.

Let's start the installation and the setup!

Become root.





 cyrus21-imapd cyrus21-common cyrus21-admin cyrus21-client sasl-bin sasl2-bin
Installing cyrus21-imapd...

The installer asks something I've not understood about an search address... I just pressed 


The installer also created the user cyrus that is in the (automatically created) group sasl, that is the “owner” of all cyrus files. At the end with ps -A you can find the new processes: cyrmaster and notifyd .

The real problem in setting up Cyrus is the authentication, just because it's not trivial and I'm a newbie, with limited knowledge about what I'm doing.

Cyrus can use different SASL (Simple Authentication and Security Layer) mechanisms, the default being sasldb (it stores usernames and passwords in the SASL secrets file sasldb), but also getpwent, kerberos4, kerberos5, PAM, rimap, shadow and LDAP are supported.

Since I don't want to define users/passwords different than the ones that access my Linux� box I choose then “shadow” mechanism so Cyrus will use Linux� passwords for authenticate.

To do so we have to tell sasl to use saslauthd as password authentication method, and then setup saslauthd to use “shadow” (or “getpwent”) as the authentication mechanism.

OK, let's start!

As root, change the Linux password of cyrus user:



Enter the password you like (and you will remember) we will use for this example “cyrus” as the cyrus administrator password.



instead of the default auxprop

remove the # remark from the line:

#admins: cyrus

this way you can administer cyrus logging in as cyrus user (what a fantasy I have!)




Uncomment the line:

# START=yes

(otherwise the saslauthd will not start at boot time, even if referenced in some /etc/rcx.d!)

and instead of MECHANISMS="pam" put MECHANISMS="shadow" this way at the boot a saslauthd -a shadow will be executed.

Once exited from your editor, restart sasl and cyrus.

To test IMAP:






-m login -p imap localhost

You are prompted for the cyrus (user) password, so enter it.

If the user cyrus is correctly authenticated, the following lines will appear:

S: L01 OK User logged in

To exit type . logout (i.e. dot space “logout”)

Now add a user named groupware and set a password for it, using your usual system tools. It should be in an unprivileged group such as nobody and does not require a login shell or a home directory.

Now I have to create the user and an IMAP in cyrus also:



--user cyrus localhost

after entering the password for the admin user cyrus, you get the prompt localhost>





lists the mailbox only just created

user.groupware (\HasNoChildren))


You can type help for a list of available commands.

You can check what has happened with:




total 12
-rw------- 1 cyrus mail          4 Oct 29 20:55 cyrus.cache
-rw------- 1 cyrus mail 155 Oct 29 20:55 cyrus.header
-rw------- 1 cyrus mail 76 Oct 29 20:55 cyrus.index

Now you should be able to connect with an IMAP client as the groupware user and see the INBOX.


In the IMAP protocol, selecting the mailbox INBOX is a magic word, a sort of “alias” for the above directory structure. The client sees INBOX, and the IMAP server maps it in the /var/spool/cyrus/mail/... folder and file structure.

  Published under the terms of the GNU General Public License Design by Interspire