This step should have been completed upon the installation of Drupal 8 for getting PHPMailer function

Install Composer

# curl -sS https://getcomposer.org/installer | php

Move Composer binary to usr bin path

# mv composer.phar /usr/bin/composer

Check Composer Version

# composer --version

Go to Drupal root Directory and execute

Drupal Installation Directory - /var/www/html

• List available PHP Version

[root@testsvr01 ~]# yum module list php

• Install Remi Repository

[root@testsvr01 ~]# yum install http://rpms.remirepo.net/enterprise/remi-release-7.rpm

[root@testsvr01 ~]# yum -y install yum-utils

• Enable PHP 8.1 Repo

root@testsvr01 ~]# yum-config-manager --enable remi-php81

• Install PHP 

[root@testsvr01 ~]# yum install php -y

• Check Current PHP Version

[root@testsvr01 ~]# php -v
PHP 7.4.33 (cli) (built: Oct 31 2022 10:36:05) ( NTS )
Copyright (c) The PHP Group
Zend Engine v3.4.0, Copyright (c) Zend Technologies
    with Zend OPcache v7.4.33, Copyright (c), by Zend Technologies

• Install yum utils 

[root@testsvr01 yum.repos.d]# yum -y install yum-utils

[root@testsvr01 ~]# yum install banner -y

[root@testsvr01 ~]# banner learnstowin

Network Diagram

The typical network diagram. The internet terminated at the modem and the modem is connected to the server/network switch through Ethernet cable. Configure the modem as Bridge mode and dial the same from the server to get the WAN IP.

• Check Disk IOPS using dd command in Linux

[root@testsvr01~]# dd if=/dev/zero of=/tmp/temp.img bs=2G count=1 oflag=dsync status=progress
2147479552 bytes (2.1 GB) copied, 3.478083 s, 617 MB/s
0+1 records in
0+1 records out
2147479552 bytes (2.1 GB) copied, 3.4785 s, 617 MB/s
[root@testsvr01~]#

• Create Sudo / Root Privilege  User

[root@testsvr01 ~]# useradd sysadmin -G wheel

• Set Password

[root@testsvr01 ~]#  passwd sysadmin
Changing password for user sysadmin. <Password >
New password: <Password >
BAD PASSWORD: The password is shorter than 8 characters
Retype new password:
passwd: all authentication tokens updated successfully.

• Find and Replace a word in a File 

[root@testserver01 opt ]#   sed -i 's/find_pattern/replace_pattern/g'  /opt/filename

• Find and Replace a word in all Files in a folder

[root@testserver01 opt ]# sed -i 's/find_pattern/replace_pattern/g'   /opt/*.filetype

• Create RSA Key pair for accessing SSH Service

[root@testserver01 ~]# ssh-keygen
Generating public/private rsa key pair.
Enter file in which to save the key (/root/.ssh/id_rsa):
Created directory '/root/.ssh'.
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /root/.ssh/id_rsa.
Your public key has been saved in /root/.ssh/id_rsa.pub.
The key fingerprint is: