Now that you have qmail up and running, we're going to add a few extras onto it. For starters, we're going to install Courier-imap/imaps along with Courierpassd. Installing IMAP will, obviously, enable IMAP connections to the mail server and it is a necessary ingredient for most popular web based mail clients such as Horde, SQwebmail and Squirrelmail. Courier-imap is the preferred IMAP server to install because it has built in support the vchkpw mail user setup that Vpopmail utilizes. In short, Courier IMAP works with Vpopmail and virtual domains. In addition to installing Courier-imap, we're going to install Courierpassd. Courierpassd is a utility that allows users to change their mailbox passwords remotely. This will come in handy when we install Squirrelmail in the next step of the installation. Courierpassd will allow your mail users to change their passwords using the Squirrelmail interface. This will give your users more power over their account settings and, more importantly, keep them from pestering you whenever they want to change their passwords. ;)

So let's start by installing Courier-imap/imaps

bunzip courier-imap-3.0.8.tar.bz2

tar xvf courier-imap-3.0.8.tar

cd courier-imap-3.0.8

./configure --prefix=/usr/local --exec-prefix=/usr/local --with-authvchkpw --without-authdaemon --without-authldap --disable-root-check --with-ssl --with-authchangepwdir=/usr/local/libexec/authlib

Hint: Since the above config line runs over 1 line, it'll be easier if you simply cut and past the entire config statement.

Note: the configure process will take a few minutes. Go grab a snack...

make && make install-strip && make install-configure

Now let's continue configuring imap...

cd /usr/local/etc

Make sure that the files "imapd" and "imapd-ssl" exist. If they do not exist, do the following:

cp imapd.dist imapd

cp imapd-ssl.dist imapd-ssl

Now let's create an SSL certificate for the IMAP-SSL server...

/usr/local/sbin/mkimapdcert

This will start and automated process that creates a self-signed imap-ssl X.509 certificate called imapd.pem. It should create this new certificate at /usr/local/share/imapd.pem. If the certificate already exists, the "mkimapdcert" tool will not let you overwrite it.

A Note on IMAP-SSL certificates: Keep in mind that since this SSL certificate is self-signed and is not from a "trusted" authority such as Verisign or Thawte, mail clients such as Outlook will give a warning when they attempt to connect to your IMAP-SSL server on port 993. The warning will state that the certificate is not from a "trusted" authority. While the warning is a bit ugly, it does NOT mean your IMAP-SSL connection is any less secure than it would be with a real certificate from Verisign or Thawte. All it means is that the SSL certificate was not generated by a company which Microsoft recognizes as a "trusted" authority. From a security standpoint, however, your IMAP-SSL server is every bit as secure as it would be if you bought the certificate from Verisign or Thawte. If the warning is too inconvenient for your purposes, you will need to purchase a "real" certificate from a "trusted" authority such as Verisign or Thawte. Be prepared to shell out a good chunk of change if you do so.

vi +68 imapd-ssl

Make sure that the following configuration exists: IMAPDSSLSTART=YES

Make sure that the following configuration exists around line 149: TLS_CERTFILE=/usr/local/share/imapd.pem

Save and exit the file.

Now we create the startup scripts...

cp /usr/local/libexec/imapd.rc /etc/init.d/imap

cp /usr/local/libexec/imapd-ssl.rc /etc/init.d/imaps

Now let's start up IMAP and IMAP SSL...

/etc/init.d/imap start

/etc/init.d/imaps start

If you run "nmap localhost", you should see both 143 and 993 now open and listening.

Now let's test it...

telnet localhost 143

Trying 192.168.1.10...
Connected to 192.168.1.10.
Escape character is '^]'.
* OK [CAPABILITY IMAP4rev1 UIDPLUS CHILDREN NAMESPACE THREAD=ORDEREDSUBJECT THREAD=REFERENCES SORT QUOTA IDLE STARTTLS] Courier-IMAP ready. Copyright 1998-2003 Double Precision, Inc. See COPYING for distribution information.
a login [email protected] my_password
a OK LOGIN Ok. (successful login!)
a logout (logs you out)
* BYE Courier-IMAP server shutting down
a OK LOGOUT completed
Connection closed by foreign host.

Hint: The "a" that you see before my login commands is required.

If you were able to log in , as in the example above, you're all set. IMAP is installed! For further testing, you can configure a mail client such as Outlook to test both the IMAP and IMAP-SSL connetion to your server. IMAPS runs on port 993.

Now that Couroier-imap is installed let's install our webmail client, Squirrelmail.

Proceed to Part 13