Installing BIND

The steps below will install the chrooted BIND and the GUI configuration tool.

1. Type in the command below to install BIND.

yum install bind-chroot system-config-bind

2. Start the named service. Learn how to start and stop services.

3. Open the TCP port 53 and UDP port 53. Learn how to configure the firewall.

Configuring BIND

The steps shows how to configure BIND using the GUI configuration tool.

1. Click System, select Administration and click Domain Name System. This will launch the BIND Configuration GUI window.

2. Click Ok to initialize BIND with default values.

3. BIND has now been initialized. We can now create a DNS zone and add DNS records.

Creating a DNS Zone

The steps below will show you how to create a DNS zone named “acme.local”.

1. To create a DNS zone, right click DNS Server, select Add and click Zone.

2. In the New Zone window, click the Ok button under Class.

3. Next, click the Ok button under Origin Type.

4. Provide the name of the zone and click Ok.

5. Review the various settings and click Ok.

6. Click Save and click Yes.

7. You now have a new DNS zone.

Creating DNS Records

The steps below describes how to create some of the most common DNS records.

Creating an A record

An A record maps a hostname to its IPv4 address.

1. Right click the zone you where you want to add an A record, select Add and click A IPv4 Address.

2. Specify the Domain Name and IPv4 Address and click Ok.

3. Click Save and click Yes.

Creating a CNAME record

A CNAME record specifies that a domain name is an alias of another domain name.

1. Right click the zone you where you want to add a CNAME record, select Add and click CNAME Alias.

2. Specify the Domain Name and Canonical Name (target domain name) and click Ok.

3. Click Save and click Yes.

Creating an MX record

An MX record specifies how Internet e-mail should be routed using SMTP.

1. Right click the zone you where you want to add an MX record, select Add and click MX Mail Exchange.

2. Specify the Mail Server Name and click Ok.

3. Click Save and click Yes.

Testing BIND

To test your BIND setup, you can use the nslookup and dig utility.

1. Type the command below in a terminal window to use nslookup

nslookup mail.acme.local localhost

Replace mail.acme.local with the domain you want to check. If your DNS server is not on localhost then change it.

2. Type in the command below to query any records using dig.

dig @localhost acme.local ANY

Replace acme.local with your own domain. If your DNS server is not on localhost then change it.

• Mozilla Firefox 2 and 3
• Microsoft Internet Explorer 7
• Microsoft Internet Explorer 6 and lower (Microsoft KB article)

Mozilla Firefox 2 and 3

1. Click Tools and click Options. This will show the Options window.

2. In the Options window, click Advanced.

3. Click the Network tab.

4. Click the Settings button. This will show the Connection Settings window.

5. In the Connection Settings window, select Manual proxy configuration and fill in the HTTP Proxy and Port fields. Next, check the Use this proxy server for all protocols. Click Ok when you are done. Click Ok again in the Options window.

Microsoft Internet Explorer 7

1. Click Tools and click Internet Options. This will show the Internet Options window.

2. In the Internet Options window, click the Connections tab.

3. In the Connections page, click the Lan settings button. This will display the Local Area Network (LAN) Settings window.

4. In the Local Area Network (LAN) Settings window, fill in the Address and Port fields and check the Bypass proxy server for local addresses. Click Ok when you are done. Click Ok again in the Internet Options window.

Installing the Java Runtime Environment (JRE)

1. Download the Java software for Linux from Sun Microsystem. Choose the RPM format.

2. Right click the downloaded file and click Properties. This will launch the Properties window.

3. In the Properties window, click the Permissions tab and check Allow executing file as program. Click Close when you are done.

4. Double click the file to execute it and click Run in Terminal. Press Spacebar until you reach the end of the text. Type in yes and press Enter to agree to the license terms and proceed with the installation.

5. Check your Java installation by typing in the command below. Note down the version.

java -version

6. If the version being used is not the one you installed, type in the command below to make it so.

ln -sf /usr/java/default/bin/java /usr/bin/java

The above would be the case if you install the Fedora Directory Server which pulls in on an old version of Java during installation.

Configuring Firefox

1. Enable Firefox to find the Java plugin by typing in the commands below in a terminal window.

cd /usr/lib/mozilla/plugins
ln -sf /usr/java/default/plugin/i386/ns7/libjavaplugin_oji.so .

2. Launch Firefox and type in about:plugins in the address bar to verify the presence of Java.

Linux Mail Server Howtos

Setting Up a Linux Email Server in an NT Domain this is the site that made it possible for me to recommend a Linux based mail solution instead of the usual Windows and Exchange solution.

Others

Selfgrowth.com is the most complete guide to information about Self Improvement, Personal Growth and Self Help on the Internet. It is designed to be an organized directory, with articles and references to thousands of other Web Sites on the World Wide Web.

Linux Distribution

• Red Hat Enterprise Linux is a Linux distribution produced by Red Hat and targeted toward the commercial market, including mainframes. Red Hat commits to supporting each version of RHEL for 7 years after its release.

• CentOS is an Enterprise-class Linux Distribution derived from sources freely provided to the public by Red Hat.

Mail Delivery and Transfer

• Postfix is an open source SMTP Server that is fast, easy to administer, flexible while at the same time being sendmail compatible enough to not upset existing users. Written by security expert Wietse Venema, it is built from the ground up to be secure.

• Dovecot is an open source IMAP and POP3 server for Linux/UNIX-like systems. It complements Postfix with its high performance, ease of administration and rock solid security.

Web Mail Access

• Apache is an open-source HTTP server supporting a wide range of operating systems including UNIX and Windows NT. Apache is a secure, efficient and extensible HTTP server that provides HTTP services in sync with the current HTTP standards.

• Squirrelmail is an open source standards-based webmail package written in PHP.

Anti-Spam and Anti-Virus

• MailScanner is an open source anti-virus and anti-spam filter for email servers. The anti-virus and anti-spam portion is delegated to third party applications.

• ClamAV is an open source (GPL) anti-virus toolkit for UNIX, designed especially for e-mail scanning on mail gateways.

• SpamAssassin is a mail filter, written in Perl, that identifies spam using a wide range of heuristic tests on mail headers and body text.

Lightweight Directory Access Protocol (LDAP)

• Fedora Directory Server is an enterprise-class Open Source LDAP server for Linux. It is full-featured, supports multi-master replication, and already handles many of the largest LDAP deployments in the world.

• OpenLDAP is an open source implementation of the Lightweight Directory Access Protocol.

• JXplorer is a standards compliant general purpose open source ldap browser that can be used to read and search any ldap directory, or any X500 directory with an ldap interface.

Active Directory Integration

• Samba is an Open Source/Free Software suite that provides seamless file and print services to SMB/CIFS clients.

System Administration

• Webmin is a web-based interface for system administration for Unix. Using any modern web browser, you can setup user accounts, Apache, DNS, file sharing and much more.

• Supports POP3, IMAP and Web mail access. These are standard services that ideally should be available in any mail system for flexible email access.

• Is extremely fast, reliable and scalable. Linux performs well and its uptime is very, very good.

• Does not require expensive hardware. Thanks to its fast and efficient services, expensive high end hardware is not necessary.

• Is very secured. The Linux operating system is very difficult to exploit. The National Security Agency even contributed to allow Linux to support even stronger levels of security.

• Has a powerful anti-spam filter. SpamAssassin uses a wide variety of local and network tests to identify spam signatures.

• Has an effective and regularly updated anti-virus. The open source nature of Clam Antivirus allows it to respond to new viruses even faster than commercial antivirus softwares.

• Has small to zero (as in free) software cost depending on your support needs. Depending on your support needs, you have the option of using a community supported Linux or a company supported one.

• Works with Microsoft Active Directory. You can integrate Microsoft Active Directory user accounts and distribution list into your Linux mail server to simplify administration.

A client asked me to reinstall their mail server. Their existing mail server using Microsoft Exchange 2000 on Windows 2000 Server was frequently down. Whenever it was up, it performed badly. It performed so bad that it took minutes just to check mails and learn they have no new mail.

The Goal

The client gave me a list of features the new mail server should have. It should flag spam mails. It should check for viruses. It should have web access. It should block several types of file attachments. And if I will not be using Microsoft Exchange, it should be integrated into Active Directory since they do not want to maintain two sets of user accounts.

They gave me a free hand on whatever hardware and software to purchase. They leave it up to me to decide if they need to upgrade to Exchange 2003 and Windows 2003 Server, or replace the old IBM Server and maintain the Exchange 2000 and Windows 2000 Server, or use a totally different solution.

The Solution

After studying their requirements, I discovered I can save them tons of cash while at the same time provide them a reliable mail solution which meets all their requirements using Linux, open source softwares, and off the shelf hardware.

So I implemented the above solution and they where very pleased with the results. They immediately noticed the improvement in response time. Mailboxes were now cleaner with the big reduction in spam mails. Virus problems was now virtually eliminated.

If you like the true story above, welcome to LinuxMail.info. This site is about helping you be able to do the same. I spent several weeks searching the internet and experimenting several configurations to achieve the requirements above using Linux. With this site, you should be able to achieve this in just a few minutes.