Howto do a netinstall of CentOS 7 (7.4.1708) – minimal server installation

Minimal net install is useful when a dedicated server is installed from a IPMI KVM or Dell iDRAC, HP iLO, IBM IMM or where the initial client side download of files need to be minimal.
For amd64 CentOS 7 the net install bootable media is located here (now the current latest release is 7.4.1708, but you can check the last directory with 7. for the time you follow this howto):

http://mirror.leaseweb.com/centos/7.4.1708/isos/x86_64/CentOS-7-x86_64-NetInstall-1708.iso

Now this version is deprecated and you could have problems downloading it, so you could try the CentOS vault – http://vault.centos.org/7.4.1708/isos/x86_64/ Just follow the instructions for downloading.
Download it and put it on a cd or usb, the boot from it and follow the steps bellow:

STEP 1) Select “Install CentOS 7” and press “Enter”

main menu
Select CentOS 7 Installation

STEP 2) Wait for the installation to boot

main menu
Booting the installation

STEP 3) This is the first step, you could choose your Country and language, English is the default.

main menu
Country and language selection

STEP 4) Setup the right time and time zone of your server, this step is important, the clock of the server is really important for your software to work properly!

main menu
Date & Time

STEP 5) Often servers are set with UTC time, which is never changed (no summer saving time!). UTC is Coordinated Universal Time and first you must select “Etc” from the first dropdown menu.

main menu
Date & Time – UTC selected

STEP 6) Next let’s configure the network, because we are doing a network installation you need Internet connection to install the CentOS 7.

main menu
Network & Host Name

STEP 7) Click to configure the selected network adapter on the right.

main menu
Configure network Adapter

STEP 8) Click on the menu “IPv4 Settings”, then choose from the dropdown menu “Manual” (technically you can leave it Automattically as the default is, but this is a server howto it is not very clever your IP to be assigned by a DHCP server, but your setup could vary). Then click on “Add” and write your IP address, network mask and gateway, then in the DNS Servers write your local (and fast!) DNS server, if you have more than one separate them with comas.

main menu
IPv Settings

STEP 9) Click “General” menu and then check the “Automatically connect to this network when it is available” – this is very important, because if you do not check, when you reboot the server, it won’t start the network! Click Save.

main menu
General Adapter settings

STEP 10) You can see the network is up and connected. Set a host name to your server and click on “Apply” and that’s all for the network configuration, click on “Done”.

main menu
Host Name setup

STEP 11) Click on “Installation Source” to setup the source of your installation files, because this is network installation this step is mandatory.

main menu
Installation Destination

STEP 12) Set the URL from where the setup will download packages and installation files. Set the nearest source to your server, you can check mirrors here:

https://www.centos.org/download/mirrors/

At present the latest version of CentOS 7 is 7.4.1708, but after a while it could be other, so browse the latest version directory, then you must choose directory “/os/” (there are probably many others, but we need especially “os”) and then “/x86_64/”. And then click on “Done”. That’s all you’ve configured the installation source, so now the setup knows where to look for packages and metadata for the installation process.

main menu
URL of the OS packages.

STEP 13) Choose your software to install. Click on “Software Selection”.

main menu
Software Selection

STEP 14) Because this howto is a minimal installation you should check “Minimal Install” , but you could choose another option below, the one suited best for your future server. And then click on “Done” to save the configuration.

main menu
Minimal Install

STEP 15) Click on “Installation Destination” to set the hard drive and partitions layout configuration for your server.

main menu
Installation Destination

STEP 16) The default is to leave the how disk to the setup to manage (make sure the “Automatically configure partitioning.” is checked), it will use the how hard drive checked from the Local Standard Disks. Check all the local disks you want to use in your server if more than one. If your disk has partitions you may be prompted to acquire free space by deleting existing partitions – be careful with this option, think twice before deleting partitions! Click on “Done” to save configuration.

main menu
Device selection – hard disk and partition configuration

STEP 17) Click on “Security policy” to setup a default security policy as selinux – use it whenever it is available!

main menu
Security Policy

STEP 18) Click on the “Standard System Security Porfile”, which will enable SELINUX security in your installation and then click “Select Profile”, after clicking the button will become grayed and the selection will have a green check in the right. Then click on “Done”.

main menu
Standard System Security Profile – SELINUX

STEP 19) We are all done and it is time to start the real installation of the system. Till now we’ve just configured the installation process. So click on “Begin Installation”.

main menu
Begin Installation

STEP 20) When the installation process is running you are prompt to set the root password and to add users. For clarity we set only the root password.

main menu
Root password setup

STEP 21) Set two times your password for the root user and then click “Done”.

main menu
Enter root password

STEP 22) The installation process is still running, just wait to finish.

main menu
Starting package installation process

STEP 23) You can see how many packets are install and the current installing packet and number.

main menu
Installing packages…

STEP 24) If everything goes with no errors and probably it will be with no errors you must click on “Reboot” to reboot the server in the newly installed OS.

main menu
Installation ready. Reboot

STEP 25) Grub2 and two options to select, the default is the latest kernel installed.

main menu
Grub2, default kernel boot

STEP 26) And the server is at login. The ssh server is also installed and you can access the server via ssh on the default port 22 and root login is permitted.

main menu
Login

One thought on “Howto do a netinstall of CentOS 7 (7.4.1708) – minimal server installation”

Leave a Reply

Your email address will not be published.