Postfix is a open source email server with high performance solution. There are many reasons to deploy Postfix Mail Transfer Agent on your environment. You can also setup Postfix to send email as an external SMTP provider like Google Apps and any other SMTP server. In this tutorial we will learn Postfix installation on Centos release 6.6 64-bit with IMAP/POP3 services like Dovecot and domains & users store information with mysql server. Now we will discuss in details how to install and configure mail server.
Prerequisites
If you have already sendmail MTA on your CentOS or RHEL, your need to uninstall it before installation of postfix MTA.
[root@mailserver ~]# yum remove sendmail
You have to add hostname entries on below host file.
[root@mailserver ~]# vim /etc/hosts 127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4 ::1 localhost localhost.localdomain localhost6 localhost6.localdomain6 192.168.100.11 mailserver.linuxpathfinder.local
Firewall and SELinux must be disabled.
You must have open/unblock standard mail ports (25, 465, 587, 110, 995, 143, and 993) that’s why disabled the iptables firewall.
[root@mailserver ~]# service iptables stop [root@mailserver ~]# service ip6tables stop [root@mailserver ~]# chkconfig iptables off [root@mailserver ~]# chkconfig ip6tables off
[root@mailserver ~]# vim /etc/sysconfig/selinux # This file controls the state of SELinux on the system. # SELINUX= can take one of these three values: # enforcing - SELinux security policy is enforced. # permissive - SELinux prints warnings instead of enforcing. # disabled - No SELinux policy is loaded. SELINUX=disabled # SELINUXTYPE= can take one of these two values: # targeted - Targeted processes are protected, # mls - Multi Level Security protection. SELINUXTYPE=targeted
Install Postfix
[root@mailserver ~]# yum install postfix
Configure Postfix
After installation, edit the postfix configuration file with vim editor (whatever you have editor). Search below mentioned lines and edit changes.
myhostname = mailserver.linuxpathfinder.local # Line no 75 | Uncomment and set your mail server mydomain = linuxpathfinder.local # Line 83 | Uncomment and Set domain name myorigin = $mydomain # Line 99 | Uncomment inet_interfaces = all # Line 116 | Set ipv4 inet_protocols = all # Line 119 | Change to all #mydestination = $myhostname, localhost.$mydomain, localhost, # Line 164 | Comment mydestination = $myhostname, localhost.$mydomain, localhost, $mydomain # Line 165 | Uncomment mynetworks = 192.168.100.0/24, 127.0.0.0/8 # Line 264 | Uncomment and add IP range home_mailbox = Maildir/ # Line 419 | Uncomment
Save the config file and exit from editor. Now start Postfix service.
[root@mailserver ~]# service postfix start [root@mailserver ~]# chkconfig postfix on
Test Postfix
We’ll create users to test postfix mail server.
[root@mailserver ~]# useradd user1 [root@mailserver ~]# passwd user1 [root@mailserver ~]# useradd user2 [root@mailserver ~]# passwd user2
Below are the configuration entered by the user. Must put the dot (.) after the message.
[root@mailserver ~]# telnet localhost smtp Trying ::1... Connected to localhost. Escape character is '^]'. 220 server.linuxpathfinder.local ESMTP Postfix ehlo localhost 250-server.linuxpathfinder.local 250-PIPELINING 250-SIZE 10240000 250-VRFY 250-ETRN 250-ENHANCEDSTATUSCODES 250-8BITMIME 250 DSN mail from:<user1> 250 2.1.0 Ok rcpt to:<user1> 250 2.1.5 Ok data 354 End data with <CR><LF>.<CR><LF> welcome to postfix mail server . 250 2.0.0 Ok: queued as AC079411B3 quit 221 2.0.0 Bye Connection closed by foreign host.
Verify Mail
Go to the user’s directory and check the new mail.
[root@mailserver ~]# cd /home/user1/Maildir/new [root@mailserver new]# ls 1439228640.Vfd00Ic19bbM70513.server.linuxpathfinder.local [root@mailserver new]# cat 1439228640.Vfd00Ic19bbM70513.server.linuxpathfinder.local Return-Path: <user1@linuxpathfinder.local> X-Original-To: user1 Delivered-To: user1@linuxpathfinder.local Received: from localhost (localhost [IPv6:::1]) by server.linuxpathfinder.local (Postfix) with ESMTP id AC079411B3 for <user1>; Mon, 10 Aug 2015 22:41:58 +0500 (PKT) Message-Id: <20150810174241.AC079411B3@server.linuxpathfinder.local> Date: Mon, 10 Aug 2015 22:41:58 +0500 (PKT) From: user1@linuxpathfinder.local To: undisclosed-recipients:;welcome to postfix server
It shows that postfix configuration is OK.
Install Dovecot
Dovecot (open source) is used for IMAP/POP3 mail services in Linux systems.
[root@mailserver ~]# yum install dovecot
Configure Dovecot
Edit the config file /etc/dovecot/dovecot.conf
[root@mailserver ~]# vim /etc/dovecot/dovecot.conf protocols = imap pop3 lmtp # line 20 | uncomment
Open the file /etc/dovecot/conf.d/10-mail.conf file
[root@mailserver ~]# vim /etc/dovecot/conf.d/10-mail.conf mail_location = maildir:~/Maildir # line 24 | uncomment
Open next config file /etc/dovecot/conf.d/10-auth.conf
[root@mailserver ~]# vim /etc/dovecot/conf.d/10-auth.conf disable_plaintext_auth = no # line 9 | uncomment and write no auth_mechanisms = plain login # line 97 | Add 'login' letter
Open next file /etc/dovecot/conf.d/10-master.conf,
[root@mailserver ~]# vim /etc/dovecot/conf.d/10-master.conf #mode = 0600 # lines 83-84 | uncomment and write 'postfix' user = postfix group = postfix
Save the config files and start dovecot service.
[root@mailserver ~]# service dovecot start Starting Dovecot Imap: [ OK ] [root@mailserver ~]# chkconfig dovecot on
Test Dovecot
Test dovecot with following configuration.
[root@mailserver ~]# telnet localhost pop3 Trying ::1... Connected to localhost. Escape character is '^]'. +OK Dovecot ready. user user1 +OK pass user1 +OK Logged in. list +OK 1 messages: 1 494 . retr 1 +OK 494 octets Return-Path: <user1@linuxpathfinder.local> X-Original-To: user1 Delivered-To: user1@linuxpathfinder.local Received: from localhost (localhost [IPv6:::1]) by server.linuxpathfinder.local (Postfix) with ESMTP id AC079411B3 for <user1>; Mon, 10 Aug 2015 22:41:58 +0500 (PKT) Message-Id: <20150810174241.AC079411B3@server.linuxpathfinder.local> Date: Mon, 10 Aug 2015 22:41:58 +0500 (PKT) From: user1@linuxpathfinder.local To: undisclosed-recipients:;welcome to postfix mail server . quit +OK Logging out. Connection closed by foreign host.
It shows that dovecot configuration is OK.
Install Squirrelmail
Before installation of squirrelmail package from yum. You must install EPEL repository on your server then install with showing below command.
[root@mailserver ~]# yum install squirrelmail
Configure Squirrelmail
Go to configuration directory of squirrelmail and start configuring with command as shown below:
[root@mailserver ~]# cd /usr/share/squirrelmail/config/ [root@server config]# ./conf.plSquirrelMail Configuration : Read: config.php (1.4.0) --------------------------------------------------------- Main Menu -- 1. Organization Preferences 2. Server Settings 3. Folder Defaults 4. General Options 5. Themes 6. Address Books 7. Message of the Day (MOTD) 8. Plugins 9. Database 10. LanguagesD. Set pre-defined settings for specific IMAP serversC Turn color off S Save data Q QuitCommand >> 1
Select 1 for organizational details.
New wizard will open and press 1 option again.
SquirrelMail Configuration : Read: config.php (1.4.0) --------------------------------------------------------- Organization Preferences 1. Organization Name : SquirrelMail 2. Organization Logo : ../images/sm_logo.png 3. Org. Logo Width/Height : (308/111) 4. Organization Title : SquirrelMail $version 5. Signout Page : 6. Top Frame : _top 7. Provider link : http://squirrelmail.org/ 8. Provider name : SquirrelMailR Return to Main Menu C Turn color off S Save data Q QuitCommand >> 1
Put your organization name.
We have tried to make the name SquirrelMail as transparent as possible. If you set up an organization name, most places where SquirrelMail would take credit will be credited to your organization.If your Organization Name includes a '
After done above changes save it and return back to your main menu. Enter option “2” to setting up of Server settings now.
SquirrelMail Configuration : Read: config.php (1.4.0) --------------------------------------------------------- Main Menu -- 1. Organization Preferences 2. Server Settings 3. Folder Defaults 4. General Options 5. Themes 6. Address Books 7. Message of the Day (MOTD) 8. Plugins 9. Database 10. Languages D. Set pre-defined settings for specific IMAP servers C Turn color off S Save data Q Quit Command >> 2
Enter “1” option now.
SquirrelMail Configuration : Read: config.php (1.4.0) --------------------------------------------------------- Server Settings General ------- 1. Domain : localhost 2. Invert Time : false 3. Sendmail or SMTP : Sendmail A. Update IMAP Settings : localhost:143 (uw) B. Change Sendmail Config : /usr/sbin/sendmail R Return to Main Menu C Turn color off S Save data Q Quit Command >> 1 The domain name is the suffix at the end of all email addresses. If for example, your email address is jdoe@example.com, then your domain would be example.com. [localhost]: linuxpathfinder.local
Enter “3” option to change Postfix MTA (SMTP)
SquirrelMail Configuration : Read: config.php (1.4.0) --------------------------------------------------------- Server Settings General ------- 1. Domain : linuxpathfinder.local 2. Invert Time : false 3. Sendmail or SMTP : Sendmail A. Update IMAP Settings : localhost:143 (uw) B. Change Sendmail Config : /usr/sbin/sendmail R Return to Main Menu C Turn color off S Save data Q Quit Command >> 3
Enter “2” to choose postfix (SMTP).
You now need to choose the method that you will use for sending messages in SquirrelMail. You can either connect to an SMTP server or use sendmail directly. 1. Sendmail 2. SMTP Your choice [1/2] [1]: 2
Now save SquirrelMail configuration and exit.
Create a Virtual Host of squirrelmail in apache configuration file as follows:
[root@mailserver ~]# vim /etc/httpd/conf/httpd.conf
Same following lines need to add at the bottom of the apache configuration file.
Alias /mywebmail /usr/share/squirrelmail <Directory /usr/share/squirrelmail> Options Indexes FollowSymLinks RewriteEngine On AllowOverride All DirectoryIndex index.php Order allow,deny Allow from all </Directory>
After changes in apache config file, you need to restart the apache services to change effect.
[root@mailserver ~]# service httpd restart
Now you have to create some users for email testing.
[root@mailserver ~]# useradd mailuser1 [root@mailserver ~]# useradd mailuser2 [root@mailserver ~]# passwd mailuser1 [root@mailserver ~]# passwd mailuser2
You may now open webmail like ip-address/mywebmail or domain-name/mywebmail. Screen should look like on your browser as shown below now put your newly created user’s credentials into mywebmail.
Squirrel Mail
You have got the access of user named ‘mailuser1’. Now compose an email from your mail box to send email to other webmail user named mailuser2. In compose mailbox, put the second user mail id in recipient, and write mail and click send button.
User1 Inbox
Logout the current user and login second test user and check email.
User2 Inbox
You will see new email to mail ID mailuser2.linuxpathfinder.local as shown.
Email Get to User2
That’s it.
, please precede it with a \. Other '
After done above changes save it and return back to your main menu. Enter option “2” to setting up of Server settings now.
Enter “1” option now.
Enter “3” option to change Postfix MTA (SMTP)
Enter “2” to choose postfix (SMTP).
Now save SquirrelMail configuration and exit.
Create a Virtual Host of squirrelmail in apache configuration file as follows:
Same following lines need to add at the bottom of the apache configuration file.
After changes in apache config file, you need to restart the apache services to change effect.
Now you have to create some users for email testing.
You may now open webmail like ip-address/mywebmail or domain-name/mywebmail. Screen should look like on your browser as shown below now put your newly created user’s credentials into mywebmail.
Squirrel Mail
You have got the access of user named ‘mailuser1’. Now compose an email from your mail box to send email to other webmail user named mailuser2. In compose mailbox, put the second user mail id in recipient, and write mail and click send button.
User1 Inbox
Logout the current user and login second test user and check email.
User2 Inbox
You will see new email to mail ID mailuser2.linuxpathfinder.local as shown.
Email Get to User2
That’s it.
will be considered the beginning of a variable that must be defined before the $org_name is printed. $version, for example, is included by default, and will print the string representing the current SquirrelMail version.[SquirrelMail]: linuxpathfinder
After done above changes save it and return back to your main menu. Enter option “2” to setting up of Server settings now.
Enter “1” option now.
Enter “3” option to change Postfix MTA (SMTP)
Enter “2” to choose postfix (SMTP).
Now save SquirrelMail configuration and exit.
Create a Virtual Host of squirrelmail in apache configuration file as follows:
Same following lines need to add at the bottom of the apache configuration file.
After changes in apache config file, you need to restart the apache services to change effect.
Now you have to create some users for email testing.
You may now open webmail like ip-address/mywebmail or domain-name/mywebmail. Screen should look like on your browser as shown below now put your newly created user’s credentials into mywebmail.
Squirrel Mail
You have got the access of user named ‘mailuser1’. Now compose an email from your mail box to send email to other webmail user named mailuser2. In compose mailbox, put the second user mail id in recipient, and write mail and click send button.
User1 Inbox
Logout the current user and login second test user and check email.
User2 Inbox
You will see new email to mail ID mailuser2.linuxpathfinder.local as shown.
Email sent to User2
That’s it.
