Apache web server

The Apache HTTP server, commonly known as Apache is a free and open-source web server, that delivers web content through the internet. As open-source software, its original source code is freely available for developers to view and collaborate. This has made Apache a favorite among developers who create and configure Apache models to expand its functionality and improve on its core features.

Why webserver

• To deliver app securely
• To remove downtime
• For load balancing

Difference between Apache web server and nginx web server

NGINX also supports reverse proxy.
Reverse proxy: A server that sits between client device [web browser] and backend server and then returning the server’s response to the client. Acts as a actual server hiding existence of characteristics of backend server.

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To install apache2

• apt install apache2
• sudo systemctl status apache2
• sudo systemctl enable apache2
• sudo systemctl start apache2

Commands

• a2enmod: To enable module
• a2ensite: To enable the site
• a2enconf: To enable configuration
• a2dismod:
• a3dissite:
• a2disconf:

Apache2 configuration overview

/etc/apache2/
|-- apache2.conf
|       `--  ports.conf
|-- mods-enabled
|       |-- *.load
|       `-- *.conf
|-- conf-enabled
|       `-- *.conf
|-- sites-enabled
|       `-- *.conf

• apache2.conf
  • Master configuration file that pulls in all other settings like modules, ports, sites,etc.
• ports.conf
  • Specifies the TCP ports Apache listens on
    • Example: Port 80 for HTTP request and 443 for HTTPs.
• mods-available and mods-enabled
  • mods-available holds all the module defination [load to load code and conf to configure code]
  • mods-enabled contains syslinks to subset actually in use
• Conf-enabled and conf-available
  • Conf-enabled holds syslinks to the active snippets.
  • conf-available store the global snippets.
• Sites available and sites enables:
  • Sites available contains all virtual hosts defination
  • sites enabled has syslinks to the ones currently served to clients
• envars
  • Define apache’s own environmetn variables [ Ex: log directory, PID file, Run user ] that get loaded when using apache2ctl or init script.
• Magic
  • Contains magic number rules for defining a file MIME type based on its initial bytes [EG: %pdf for pdf]
• logrotate
  • It determines for how much time we need to place the logs.
  • This is the linux utility that manages the automatic rotation, compression and removal of log files.
  • Prevents log files from consuming excessive disk space.

To load a website in apache2

• Download a site from toolplate : download>>inspect >> network >> name.zip file >>copy URL of the of the zip file here is 2103_central.zip. This file name is based on the template name.

• wget /tmp or any location you want to.
• unzip the URL by using command unzip -R filename.
• Copy the unzipped files to /srv/dirname
• Now copy the /etc/apache2/000-default file and create a new file for example newfile.conf and in file change root = /srv/dirname. This is the path where you have copied file earlier.
• Now activate the site a2ensite newfile.conf
• a2dissite 000-default.conf
• chown -R www-data:www-data /srv/: When apache reads static files like HTML, CSS and javascript it as www-data user. So we need to change ownership of directory to www-data.
• vim /etc/apache2/apache2.conf
  • #Simply uncomment this line
• Now systemctl restart apache2
• Now that custom website will be launched.
• To access locally curl localhost.

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Linux commands[2]

1. Linux Links
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6. Sudo
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1. To see Ip address of the machine
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Linux Introduction

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