Magento 2.2.x technology stack requirements

Solution:

Pre-requisite : for the magneto installation

• https://devdocs.magento.com/guides/v2.2/install-gde/prereq/prereq-overview.html

Operating systems (Linux x86-64)

• A Linux distribution such as RedHat Enterprise Linux (RHEL), CentOS, Ubuntu, Debian, and so on.

Memory requirement

• Upgrading the Magento applications and extensions you obtain from Magento Marketplaces and other sources can require up to 2GB of RAM. 
• If you are using a system with less than 2GB of RAM, we recommend you create a swap file; otherwise, your upgrade might fail.

Composer (latest stable version)

• Composer is required for developers who wish to contribute to the Magento 2 codebase or anyone who wishes to develop Magento extensions.

Web servers

• Apache 2.2 or 2.4
  In addition, you must enable the Apache mod_rewrite and mod_version modules. The mod_rewritemodule enables the server to perform URL rewriting. The mod_version module provides flexible version checking for different httpd versions. For more information, see our Apache documentation.
• nginx 1.x

Database

• MySQL 5.6, 5.7
• Magento is also compatible with MySQL NDB Cluster 7.4.*, MariaDB 10.0, 10.1, 10.2, Percona 5.7, and other binary-compatible MySQL technologies.

PHP

7.0.0–7.0.12	7.0.13–7.0.x	7.1.x

Required PHP extension

• The CentOS and Ubuntu PHP installation instructions include a step for installing these extensions.
• bc-math (Magento Commerce only for 2.2.0 - 2.2.3. Magento Commerce and Magento Open Source as of 2.2.4.)

• ctype
• curl
• dom
• gd, ImageMagick 6.3.7 (or later) or both
• intl
• mbstring
• mcrypt
• hash
• openssl
• PDO/MySQL
• SimpleXML
• soap
• spl
• libxml
• xsl
• zip
• json
• iconv

PHP OPcache

• strongly recommend to install PHP OPcache is enabled for performance reasons. 
• The OPcache is enabled in many PHP distributions. To verify if it is installed, see our PHP documentation for CentOS or Ubuntu.
• If you must install it separately, see the PHP OPcache documentation.

PHP settings

• We recommend particular PHP configuration settings, such as memory_limit, that can avoid common problems when using Magento.
• For more information, see Required PHP settings.

SSL

• A valid security certificate is required for HTTPS.
• Self-signed SSL certificates are not supported.
• Transport Layer Security (TLS) requirement - PayPal and repo.magento.com both require TLS 1.1 or later:
• More information about PayPal
• More information about repo.magento.com

Mail server

• Mail Transfer Agent (MTA) or an SMTP server

Magento can use the following technologies:

• Redis version 3.2 (compatible with 2.4+ ) for page caching and session storage
• Varnish version 4.x or 5.0
• memcached latest stable version for session storage with either memcache or memcached PHP extensions (latest stable version)

Magento can use the following technologies:

• Redis version 3.2 (compatible with 2.4+ ) for page caching and session storage
• Varnish version 4.x or 5.0
• memcached latest stable version for session storage with either memcache or memcached PHP extensions (latest stable version)

Magento Commerce only

• Elasticsearch
  Magento Commerce version 2.2.x supports the following Elasticsearch versions:
  • Elasticsearch 5.x
  • Elasticsearch 2.x
  Magento 2.2.3 uses Elasticsearch PHP client version 5.1. Before version 2.2.3, Magento used PHP client version 2.0.
• RabbitMQ 3.5.x (compatible with 2.0 and later)
  RabbitMQ can be used to publish messages to queue and to define the consumers that receive the messages asynchronously.
• Three master databases
  These master databases provide scalability advantages for different functional areas of the Magento application, such as checkout, orders, and all remaining Magento2 application tables.

Optional but recommended:

• php_xdebug2.2.0> or later (development environments only; can have an adverse effect on performance)