Red Hat Enterprise Linux 7 (RHEL7) Installation Steps with Screenshots

Red Hat Enterprise Linux 7 (RHEL7) Installation Steps with Screenshots

Redhat has recently released RHEL7 Operating system.  Some of the Changes in RHEL7 are listed below as compare with RHEL 6 .

• Default root file system is XFS
• Linux 3.10 kernel.
• A new systemctl command replaces chkconfig and service, although scripts allow you to still use the legacy commands.
• Docker: The biggest new addition to RHEL 7 is tight integration of Docker, the explosively popular application-virtualization technology.
• Boot-loader GRUB2
• Samba 4.1 and BTRFS makes an appearance

In this article we will go through the installation steps of RHEL 7, we will be installating using DVD or ISO file .

Step:1 Download the Binary DVD ISO File

Only the registerd users & who have the subscription on redhat portal can download the iso file of RHEL7. 

Use the link " Download RHEL7 Binary Dvd iso file" Once you have download the ISO file , Burn the ISO file to DVD media or create bootable USB media as per requirement.

Step:2 Boot the system from the bootable disk and select "Install Red Hat Enterprise Linux 7.0" as shown below :

Step:3 Select the language that will be used during installation

Click on Continue...

Step:4 Set Customize installation options:

• Adjust Date & Time, Keyboard, and Language Support preferences under Localization.
• Modify Installation Source, Software Selection, and Network Configuration  options   under Software.
• Under System : I have created customize partition table by clicking on the Installation Destination , preview of my customize partition table shown below :

Now Finally click on "Begin Installation"

Step:5 Set the root password & Create a system user

As we can see above installation has started. Once the installation is completed it will ask fro reboot.

Step:6 Reboot the Machine , after installation is completed :

click on Reboot

Step:7 Console after OS Installation

Mail Server Components : MTA , MDA & MUA

Overview

In general, all email servers consists of three main components: MTA , MDA & MUA. Each components plays a specific role in the process of moving and managing email messages. While most users are only aware of the specific email program they use to receive and send messages, each one is important for ensuring that email arrives at the correct destination.

Mail Transport Agent(MTA)

A Mail Transport Agent (MTA) transports email messages between hosts using SMTP. A message may involve several MTAs as it moves to its intended destination.

While the delivery of messages between machines may seem rather straightforward, the entire process of deciding if a particular MTA can or should accept a message for delivery is quite complicated. In addition, due to problems from spam, use of a particular MTA is usually restricted by the MTA's configuration or the access configuration for the network on which the MTA resides.

Many modern email client programs can act as an MTA when sending email. However, this action should not be confused with the role of a true MTA. The sole reason email client programs are capable of sending email like an MTA is because the host running the application does not have its own MTA. This is particularly true for email client programs on non-UNIX-based operating systems. However, these client programs only send outbound messages to an MTA they are authorized to use and do not directly deliver the message to the intended recipient's email server.

Since Red Hat Enterprise Linux offers two MTAs, Postfix and Sendmail, email client programs are often not required to act as an MTA. Red Hat Enterprise Linux also includes a special purpose MTA called Fetchmail.

Mail Delivery Agent (MDA)

A Mail Delivery Agent (MDA) is invoked by the MTA to file incoming email in the proper user's mailbox. In many cases, the MDA is actually a Local Delivery Agent (LDA), such as mail or Procmail.

Any program that actually handles a message for delivery to the point where it can be read by an email client application can be considered an MDA. For this reason, some MTAs (such as Sendmail and Postfix) can fill the role of an MDA when they append new email messages to a local user's mail spool file. In general, MDAs do not transport messages between systems nor do they provide a user interface; MDAs distribute and sort messages on the local machine for an email client application to access.

Mail User Agent(MUA)

A Mail User Agent (MUA) is synonymous with an email client application. An MUA is a program that, at a minimum, allows a user to read and compose email messages. Many MUAs are capable of retrieving messages via the POP or IMAPprotocols, setting up mailboxes to store messages, and sending outbound messages to an MTA.

MUAs may be graphical, such as Evolution,thunderbird & Outlook, or have simple text-based interfaces, such as Mutt.