0 Quick Linux Server Installation

Before proceeding to install, update the necessary packages with debian with this command.

apt-get update

#### Installing Apache + PHP ####

Apache is one of the most famous web server which runs on most linux based servers by webhosting companies . With just few commands you can configure apache to run with PHP 5.

apt-get install apache2 php5 libapache2-mod-php5

Apache configuration file is located at: /etc/apache2/apache2.conf and your web folder is /var/www

To check whether php is installed and running properly, just create a test.php in your /var/www folder with phpinfo() function exactly as shown below.

nano /var/www/test.php

# test.php

<?php phpinfo(); ?>

Point your browser to http://ip.address/test.php or http://domain/test.php and this should show all your php configuration and default settings.

You can edit necessary values or setup virtual domains using apache configuration file.

Enabling GD Library with PHP

If you want to use CAPTCHA or for dynamic image generation with php scripts for image verification to stop SPAM or automated robots, then it is absolutely necessary to get php gd library installed with php. Here is the command

apt-get install php5-gd

Thats it!! Point your browser to http://domain/test.php and the php configuration settings will show GD library will be enabled for PNG, GIF, JPG etc.

Enabling Mod Rewrite with .htaccess

Do you use mod-rewrite from apache to rewrite friendly URLs ?? This must be absolutely necessary for the rewrite module to get enabled in your apache, especially if your blog, forum script uses rewriting engine to generate friendly URLs in your site.
Note that default apache2 installation does not come with mod-rewrite. Here is how you enable it. Issue the following command

# a2enmod rewrite

Once you run this command, apache will tell you that this rewrite module is enabled. You can find mod_rewrite enabled and show up in your test.php file.

I often experienced page not found 404 error with debian/ubuntu versions eventhough your apache runs with mod-rewrite. To fix this, you will need to edit the following file to make some changes.

nano /etc/apache2/sites-enabled/000-default

Find the following and change AllowOverride from None to All

<Directory /var/www/>
Options Indexes FollowSymLinks MultiViews
AllowOverride All
Order allow,deny
allow from all
# Uncomment this directive is you want to see apache2's
# default start page (in /apache2-default) when you go to /
#RedirectMatch ^/$ /apache2-default/

Upload the .htaccess file to your server and restart apache. /etc/init.d/apache2 restart

Make sure your .htaccess file has 644 permission as otherwise you get permission denied error.

#### Installing MySQL Database Server ####

Installing mysql database server is always necessary if you are running a database driven ecommerce site. Remember running mysql server to a fair extend requires atleast 256mb of RAM in your server. So unless you are running database driven sites you dont absolutely need mysql. The following commands will install mysql 5 server and mysql 5 client.

apt-get install mysql-server mysql-client php5-mysql

The configuration file of mysql is located at: /etc/mysql/my.cnf

Creating users to use MySQL and Changing Root Password

By default mysql creates user as root and runs with no passport. You might need to change the root password.

To change Root Password

mysql> USE mysql;
mysql> UPDATE user SET Password=PASSWORD('new-password') WHERE user='root';

To Create User

You must never use root password, so you might need to create a user to connect to mysql database for a PHP script. Alternatively you can add users to mysql database by using a control panel like webmin or phpMyAdmin to easily create or assign database permission to users. We will install Webmin and phpmyadmin during later once we complete basic mail LAMP installation.

PhpMyAdmin Installation

PhpMyAdmin is a nice web based database management and administration software and easy to install and configure under apache. Managing databases with tables couldnt be much simpler by using phpmyadmin.

All you need to do is:

apt-get install phpmyadmin

The phpmyadmin configuration file is located at: /etc/phpmyadmin folder.

To setup under apache all you need to do is include the following line in /etc/apache2/apache2.conf

Include /etc/phpmyadmin/apache.conf

Now restart apache: /etc/init.d/apache2 restart

Point your browser to: http://domain/phpmyadmin

Thats it!! MySQL and phpMyAdmin is Ready !!! Login with your mysql root password and create users to connect to database from your php script.

#### Mail Server Installation ####

  1. Postfix (Mail Transfer Agent MTA)
  2. Dovecot (IMAP/POP3 Server)
  3. SASL Authentication with TLS (Authenticate before sending mail outside network in Outlook)
  4. Squirrel Mail (Popular Web based Email)

As a beginner to linux it took about almost a month for me for proper installation of mail server and fixing necessary problems. I had real nightmares to configure this and so i decided that my hardwork would be helpful to linux community.

Note: If you install Postfix/Dovecot mail server you will ONLY be able to send mail within your network. You can only send mail externally if you install SASL authentication with TLS. As otherwise you get nasty "Relay Access Denied" error.

Install Postfix MTA (Mail Transfer Agent)

First install postfix package along with sasl with apt-get

apt-get install postfix postfix-tls libsasl2 sasl2-bin libsasl2-modules popa3d

During installation, postfix will ask for few questions like name of server and answer those questions by entering your domain name and select Internet site for postfix.

Postfix configuration file is located at:/etc/postfix/main.cf. You can edit this file using popular text editor nano /etc/postfix/main.cf

Start or Restart Postfix Server:

/etc/init.d/postfix restart
/etc/init.d/postfix stop
/etc/init.d/postfix start

Install Dovecot

Dovecot is one of the popular POP3/IMAP server which needs MTA like Postfix to work properly.

apt-get install dovecot

In some linux versions, the above might not work so you can install by specifying individual package names.

apt-get install dovecot-imapd dovecot-pop3d dovecot-common

Dovecot configuration file is located at: /etc/dovecot/dovecot.conf

Before we proceed we need to make some changes with dovecot configuration file. Double check the following entries in the file if the values are entered properly.

nano /etc/dovecot/dovecot.conf

# specify protocols = imap imaps pop3 pop3s protocols = pop3 imap
# uncomment this and change to no.

disable_plaintext_auth = no

pop3_uidl_format = %08Xu%08Xv

I have noticed that in some ubuntu versions, most of the above parameters are not specified. You will need to insert the values if not specified or left empty. If you dont uncomment and change disable_plaintext_auth to no, you will get "plain text authentication error" from outlook or mail clients.

Now, create a user to test our pop3 mail with outlook:

adduser <user_name>

Caution: Always create a separate user to test your mail or ftp. DO NOT LOGIN WITH ROOT ACCESS.

Restart Dovecot:

/etc/init.d/dovecot restart

Now, you can use your outlook express to test whether your new mail server is working or not. Just enter username: <user_name> with password in outlook.

Remember you will NOT be able to send email outside your network, you will be only be able to send within your domain or local network. If you attempt to send email you get nasty "relay access denied" error from outlook express. However, you should have no problems in receiving your email from outlook. Inorder to send email external email you will need to configure SASL authentication as described below.

Configure SASL Authentication with TLS

SASL Configuration + TLS (Simple authentication security layer with transport layer security) used mainly to authenticate users before sending email to external server, thus restricting relay access. If your relay server is kept open, then spammers could use your mail server to send spam. It is very essential to protect your mail server from misuse.

Let us set up SMTP authentication for our users with postfix and dovecot.

Edit the postfix configuration file /etc/postfix/main.cf and enter the few lines to enable authentication of our users

smtpd_sasl_auth_enable = yes smtpd_sasl_local_domain = yourdomain.com smtpd_recipient_restrictions = permit_mynetworks,permit_sasl_authenticated,reject_unauth_destination smtpd_sasl_security_options = noanonymous

On the Dovecot side you also need to specify the dovecot authentication daemon socket. In this case we specify an absolute pathname. Refer to this postfix manual from http://www.postfix.org/SASL_README.html

Edit /etc/dovecot/dovecot.conf

Look for the line that starts with auth default, before that insert the lines below.

auth default {
mechanisms = plain login
passdb pam {

userdb passwd {
socket listen {
client {
path = /var/spool/postfix/private/auth

mode = 0660

user = postfix

group = postfix




Now, rename previous auth default to auth default2. If you dont rename this then dovecot server will give you error like multiple instances of auth default.

Now restart all the components of mail server.

/etc/init.d/saslauthd restart
/etc/init.d/postfix restart
/etc/init.d/dovecot restart

Test whether your mail server works or not with your outlook express. Configure a user with a user name <user_name> (without @domain) and make sure that you select my server requires authentication. Under settings select same as incoming mail server


  1. If you dont enable My server requires authentication in outlook you cannot send emails to external recipients and you get relay access deniederror.
  2. Do not use root login to login to your mail server.
  3. Dont forget to create a new user before you authenticate using outlook.
Forwarding Mails

Ever wondered how to forward your mails especially if you are a webmaster managing number of sites. You might need to forward any email sent to your primary email address. Its that easy. Just create a .forward file on your home directory. Insert list of emails addresses separated by commas, where you want to get forwarded.

Login as user and type

echo 'destination_email_address' > .forward

or you can use nano to create .forward file. Just Delete .forward file if you dont want any forwarding.

Installing Squirrel Web Mail

Squirrel mail is one of the most popular web based email with very friendly interface. Squirrel mail works without mysql database very easy to install and configure under apache2..

Note: It is recommended to have apache and php installed before you install squirrelmail.

apt-get install squirrelmail

Squirrelmail configuration file is located in: /etc/squirrelmail/ folder. By default all settings are preloaded.

# Run squirrelmail configuration utility as ROOT

Now we want to setup to run under apache. Edit apache configuration file /etc/apache2/apache2.conf and insert the following line:

Include /etc/squirrelmail/apache.conf

Thats it. Your webmail is ready !!!.
Point your browser to: http://yourdomain/squirrelmail

Create a separate local user and login as a new user.


Mail Server Problems in Logs

Always refer to logs located in /var/log/mail.log so that you can identify what the problem is before you can troubleshoot.

#### Webmin - Server Control Panel ####

Webmin is a nice server control panel available free of charge. It is similar like cpanel or plesk to manage your server. Download the latest version of webmin from the main site (www.webmin.com)

wget http://downloadpath/webmin-x.x.xx.tar.gz
tar xzf webmin-x.x.x.tar.gz
cd /webmin-x.x.x

The installation program will ask series of questions and most values will be automatically set by default.

Once done, point your browser to:
http://ip.address:10000 or http://www.domainname:10000

Login into your webmin and you can do almost anything with your server.

#### Webalizer Installation ####

Webalizer is a visitor statistics software shows you nice graphic based on visitors, hits and pageviews of your site. It is indeed very easy to configure and run webalizer under apache. Webalizer runs as a daily cron job to monitor your server stats.

apt-get install webalizer

Now edit the webalizer configuration file located at: /etc/webalizer.conf and locate a line with LogFile /var/log/apache/access.log.1 and change to the correct name access.log as shown below.

LogFile /var/log/apache2/access.log

and the bin of webalizer is located at /usr/bin/webalizer which is automatically scheduled to run daily as cron job.

To run webalizer manually.


Point your browser to http://domain/webalizer and you must see some pretty nice visitor statistics of your site.

#### Installing FTP Server (VSFTP) ####

You will need a simple ftp server to upload and download your web files. i specially like vsftp server because not only it is very easy to configure but also runs faster than other ftp peers with good connection speed.

apt-get install vsftpd

Configuration file is located at: /etc/vsftpd.conf

Change the following settings in /etc/vsftpd.conf so that you allow local users and allow write using ftp.

# Uncomment this to allow local users to log in.
# Uncomment this to enable any form of FTP write command.

Before you connect using ftp client, you will need to create local users and group. Do not upload files using root.

# CD to /home/<user> and create a symbolic link to /var/www as this is the public html folder.
ln -s /var/www www

#change ownership /var/www to user
chown -R <user> /var/www

#Change to 755 permissions
chmod -R 755 /var/www

Now you can connect to ftp and upload files. Once you upload all necesarry files in the public html folder, make sure all the files have 755 permission as otherwise you will get permission denied/forbidden error from apache.

Enabling VSFTP to Show Dotted Files

By default, vsftp does not show dotted files in the server, especially .htaccess, eventhough you have successfully uploaded the files. This could be frustrating especially if you are using .htaccess for authentication or rewriting friendly URLs. To fix this just add force_dot_files=YES in your vsftp configuration file/etc/vsftpd.conf

# Activate directory messages - messages given to remote users when they
# go into a certain directory.

Restart the vsftp server /etc/init.d/vsftpd restart.

Webmin Package: VSFTP also available as webmin package. You can easily change settings from webmin for vsftp.

#### ClamAV - Antivirus Software ####

Linux based systems are often vulnerable to trojans, worms and viruses. It is often to be on the safer side to scan your server using freely available ClamAV antivirus available for linux

apt-get install clamav

To scan necessary files

clamscan -R /folders

-R is recursive and is optional

To update virus database:


Running as Cron Daily Job

To run antivirus as a cron job (automatically scan daily) just run crontab -e from your command line. Then add the following line and save the file.

02 1 * * * root clamscan -R /var/www

This will run the cron job daily @ 1.02 AM by scanning the public html. You can change the folder to whatever you want for mail etc.

#### Quick IP Tables Firewall ####

Without firewall there is no absolute security for your server. Atleast i would recommend a simple firewall that would employ packet filtering and block off unnecessary ports in your server using IP tables.

apt-get install iptables

I found Quick n Dirty Firewall
(http://wiki.vpslink.com/index.php?title=HOWTO) pretty interesting. You can copy and run the shell script to set up your quick firewall.

Remember not to block important ports like
21 (ftp)
22 (SSH)
23 (Telnet)
25 110 (email)
443 (SSL http or https)
993 (imap ssl)
995 (pop3 ssl)
10000 (webmin)
80 (http)

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