Steps to do after minimal installation of RHEL/CentOS

Steps to Do After Minimal RHEL/CentOS 7 Installation

Configure Network with Static IP Address

First thing you need to do is to set the static ip address for the system.

Use the following command to check your network adapter name.

[root@localhost ~]# ip a

Now you need to edit the network configuration file

[root@localhost ~]# vi /etc/sysconfig/network-scripts/ifcfg-eno16777736

Now add the following lines to the file

ONBOOT=yes
BOOTPROTO=static
IPADDR=192.168.5.123
NETMASK=255.255.255.0
GATEWAY=192.168.5.1
DNS1=8.8.8.8
DNS2=8.8.4.4

Now save the file and exit.

Restart the network service

Execute the following command to restart the network service.

[root@localhost ~]# service network restart

Set Hostname of Server

To check the current hostname use the following command

[root@localhost ~]# echo $HOSTNAME

Now you can edit the /etc/hostname file to change the hostname of the server

After changing the hostname, verify the hostname using the following command

[root@localhost ~]# hostname

Update CentOS Minimal Install

Update your system by executing the following command

[root@localhost ~]# yum update

Install Command Line Web Browser Links

In CentOS 7 minimal there is no GUI, to browse the internet you can use only terminal.

To install links web browser

[root@localhost ~]# yum install links

Install Apache HTTP Server

Use the following command to install httpd server

[root@localhost ~]# yum install httpd

To allow httpd service through firewall

[root@localhost ~]# firewall-cmd --add-service=http
[root@localhost ~]# firewall-cmd --reload

Now add the httpd service to start automatically when system boots.

[root@localhost ~]# systemctl start httpd.service
[root@localhost ~]# systemctl enable httpd.service

Verify the Apache HTTP Server by using links command line web browser

[root@localhost ~]# links 127.0.0.1

Install MariaDB Database

Run the following command to install MariaDB

[root@localhost ~]# yum install mariadb-server mariadb

Start and configure MariaDB server to start automatically at boot.

[root@localhost ~]# systemctl start mariadb.service
[root@localhost ~]# systemctl enable mariadb.service

Allow service MariaDB through firewall.

[root@localhost ~]# firewall-cmd --add-service=mysql

To secure MariaDB server

Execute the following command to secure MariaDB server.

[root@localhost ~]# /usr/bin/mysql_secure_installation

Install and Configure SSH Server

SSH server will be installed during the minimal installation

Now you need to edit the ssh configuration file

[root@localhost ~]# vi /etc/ssh/ssh_config

Change the desired port number with the default port number “ 22”

Uncomment the protocol and remove 1 from the protocol so that protocol “ 2” is used which is more secure than protocol 1.

Change the permit rootlogin to “ no” from the default yes

After editing save the file and exit

Now restart the ssh server

[root@localhost ~]# systemctl restart sshd.service

Install GCC (GNU Compiler Collection)

GCC stands for GNU Compiler Collection developed by GNU Project that support various programming languages. It is installed by default in CentOS Minimal Install,if not installed. To install gcc compiler run the below command.

[root@localhost ~]# yum install gcc

Install Java

To install java, run the following command

[root@localhost ~]# yum install java

To check the java version
Execute the following command to check the java version.

[root@localhost ~]# java -version

Installing Wget

wget is a command line utility that downloads content from web servers. It is an important tool you must have to download web contents or any files using wget command.

To install wget

[root@localhost ~]# yum install wget

Installing Telnet

To install Telnet, run the following command

[root@localhost ~]# yum install telnet

Enable Third Party Repositories

To download third party tools and packages you need third party repositories

To install

[root@localhost ~]# yum install epel-release

Install 7-zip

7-zip is tool which compress and extract files of all known types.

[root@localhost ~]# yum install p7zip

Install NTFS-3G Driver

A very useful NTFS driver called NTFS-3G is available for most of the UNIX-like distribution. It is useful to mount and access Windows NTFS file system.

To install

[root@localhost ~]# yum install ntfs-3g

Install Vsftpd FTP Server

VSFTPD stands for Very Secure File Transfer Protocol Daemon is a FTP server for UNIX-like System. It is one of the most efficient and secure FTP Server.

[root@localhost ~]# yum install vsftpd

Edit the configuration file ‘ /etc/vsftpd/vsftpd.conf‘

[root@localhost ~]# vi /etc/vsftpd/vsftpd.conf

Edit a few fields and leave other as it is

anonymous_enable=NO
local_enable=YES
write_enable=YES
chroot_local_user=YES

Next restart vsftpd and enable to start at boot time.

[root@localhost ~]# systemctl restart vsftpd
[root@localhost ~]# systemctl enable vsftpd

Install and Configure sudo

sudo is commonly called as super do is a program for UNIX-like operating system to execute a program with the security privileged of another user.

To configure sudo

[root@localhost ~]# vi sudo

Uncomment the wheel group configuration line to make the wheel group users to run all commands

Install and Enable SELinux

SELinux stands for Security-Enhanced Linux is a security module at kernel level.

To install

[root@localhost ~]# yum install selinux-policy

Check SELinux Mode.

[root@localhost ~]# getenforce

For debugging, set selinux mode to permissive temporarily. No need to reboot.

[root@localhost ~]# setenforce 0

After debugging set selinux to enforcing again without rebooting.

[root@localhost ~]# setenforce 1

Install Rootkit Hunter

Rootkit Hunter abbreviated as Rkhunter is an application that scan rootkits and other potentially harmful files in Linux systems.

To install

[root@localhost ~]# rkhunter

To scan harmful files in linux systems

[root@localhost ~]# rkhunter --check