The posts provide a step by step installation procedure for CentOS / RHEL 7. We have used CentOS 7.3 image for the purpose of this post.
Anaconda
- Is the installation program used by CentOS / RHEL and other Linux distributions
- Runs in textual or graphical mode
- Supports installation from local or remote sources – CD, DVD, USB drive, or images stored on a hard drive, NFS, HTTP, or FTP
- The installation can be automated with Kickstart for unattended installation.
Installation Menu
The installation menu shown below is the first screen you would see while installing CentOS 7.
The default option of Test this media & install CentOS Linux 7 is automatically selected within 60 seconds.
Install CentOS Linux 7
Select this option to use the graphical installation program to install CentOS Linux 7.
Test this media & install CentOS Linux 7
Use this default option to check the integrity of the installation media before starting the installation. Testing takes a few extra minutes but is worthwhile if you have concerns about corruption or errors with the media.
Welcome to CentOS Linux 7 screen
In the left-hand box, select the language to use for the installation. The language becomes the default language for the operating system. The language is also used to target the time zone configuration later during the installation process.
In the right-hand box, select the locale. Scroll down if necessary and click Continue to display the INSTALLATION SUMMARY screen.
Installation Summary
The Installation Summary window appears. The interface is a hub-and-spoke model rather than the linear model used in previous releases of CentOS. You can select any option in any order.
Only those options with the warning icon must be configured. A message associated with the warning appears at the bottom of the screen. Only the SYSTEM option has a warning in this example, which indicates you must select the installation destination disks.
After all installation options are configured, click Begin Installation.
Date and Time configuration
Selecting DATE & TIME from the INSTALLATION SUMMARY screen displays the screen shown below. Select the appropriate time zone by selecting the country and city closest to the location of your system.
To select the time zone, either click the map or select from the Region and City drop-down menus. You can also select Etc at the bottom of the Region menu and then select your time zone in the City menu adjusted to Greenwich Mean Time (GMT).
At the bottom of the screen, you can manually adjust the date and time as needed.
After you have made your selection, click Done to return to the INSTALLATION SUMMARY screen.
NTP configuration
You must be connected to a network before you can enable NTP. Move the Network Time switch to the ON position and click the configuration icon beside it to set the date and time by using NTP. You can then select which NTP servers to use.
After you have made your selection, click Done to return to the INSTALLATION SUMMARY screen.
Keyboard Layout
The language you selected in the welcome screen is listed as the keyboard layout in the left pane. To add support for any additional keyboards for your system, click the + button at the bottom of the screen. To delete a keyboard layout, select the layout in the left pane and click the – button at the bottom of the screen.
Type some text in the text box on the right to test a layout and to confirm that your selection functions correctly.
Click the Options button to configure layout switching options. Click Done to return to the INSTALLATION SUMMARY screen.
Language Support
Select this screen to install support for additional locales and language dialects. Select a language in the left-hand box, or type in the search box, and then select one or more locales in the right-hand box.
Click Done to return to the INSTALLATION SUMMARY screen.
Software installation source
On this screen, you can specify locally available installation media or a network location.
Selecting the Software to Install
Selecting SOFTWARE SELECTION from the INSTALLATION SUMMARY screen displays the screen shown below. From this screen, you can specify which software packages you want to install.
The Minimal Install base environment is the default environment. It contains only the minimum set of packages required to run CentOS 7.
Add-ons for Selected Environment
For each Base Environment, you can select from a list of specific Add-Ons in the right pane.
Installation Destination
From the installation destination screen, you can specify where to install the software and also configure the storage. The destination can be locally attached disk(s) or network disk(s) like iSCSI.
Storage options – Automatic partitioning
Upon selecting the destination for installation you can configure the partitioning scheme on the disk. Most of the times using the automatic partitioning option suffice our needs. Automatic disk partitioning creates :
1. 500 MB partition for an XFS file system that contains /boot.
2. A logical volume for an XFS file system that contains the root file system (/).
3. A logical volume for an XFS file system that contains the /home file system (if the selected disks are larger than 50 GB in total).
4. A logical volume for a swap partition
For the logical volumes, the default volume group name is ol. The logical volume names are ol-home, ol-swap and ol-root for home, swap and root respectively.
Network and Hostname Configuration
From this screen, you can configure networking features for your system. At the bottom of this window, you can also set the hostname for your system.
You need to configure a network only if network access is required when your system boots for the first time. Otherwise, you can configure the network after the installation is complete.
By default, the IP settings for a network interface are configured automatically by using DHCP for IPv4, and the Automatic method for IPv6. To edit the connection, click the Configure button to display the connection settings window as shown in the next slide.
Begin the Installation
Once you have done all the settings, you can begin the installation from the INSTALLATION SUMMARY screen. You will have to set a root password on the installation screen here. Optionally, you can also create another non-root user account. You will have to reboot the system once you have completed the installation.