NGINX and WordPress: A Beginner’s Q&A Guide

Preface

After experiencing great success with WordPress sites hosted on companies using NGINX, I decided to give it a try on my own. Fortunately, my experience has been positive thus far. However, when I initially began, I wished I had access to a Q&A resource that could answer some of my questions. As such, I’ve compiled one to help others who may be starting out with NGINX and WordPress.

What is NGINX?

NGINX is an open-source web server software that is designed to serve web pages and other content on the internet. It was first developed by Igor Sysoev in 2002 and has since gained popularity due to its ability to handle high traffic volumes, its reliability, and its ease of use. NGINX is used by millions of websites worldwide, including many of the world’s largest and most high-traffic sites. In addition to its web server capabilities, NGINX can also be used as a load balancer, reverse proxy, and HTTP cache, making it a versatile tool for managing and optimizing web traffic. NGINX is available under a permissive BSD-like license and is maintained by a community of developers and contributors.

Where is NGINX?

NGINX is a software application that can be installed and run on a variety of operating systems, including Linux, Unix, Windows, and macOS. The software itself does not have a physical location, but it can be installed and configured on servers located in data centers or other locations around the world. Many web hosting providers offer NGINX as an option for customers who want to use it as their web server, while others may require customers to install and configure it themselves. Additionally, NGINX can be used as a reverse proxy and load balancer to distribute traffic across multiple servers or applications, further adding to its flexibility and ubiquity.

Why NGINX?

NGINX was created to address the limitations and performance issues of traditional web servers, particularly in handling high volumes of traffic and concurrent connections. Igor Sysoev, the creator of NGINX, initially designed the software to solve these problems for a Russian web portal that he was working on at the time. NGINX was designed to be lightweight, efficient, and highly scalable, with a focus on delivering fast and reliable performance. Over time, NGINX has evolved to become a versatile tool for managing web traffic, with features like load balancing, reverse proxying, and HTTP caching, which further enhance its capabilities. Today, NGINX is widely used by businesses and organizations of all sizes, from small startups to some of the world’s largest websites, to improve the performance and reliability of their web applications and services.

How is NGINX good for WordPress?

NGINX is a popular choice for running WordPress sites because it is known for its high performance, reliability, and scalability. Here are some ways in which NGINX can be beneficial for WordPress:

Speed: NGINX is designed to handle a high volume of traffic and concurrent connections, making it well-suited for serving WordPress sites. It is known for its fast processing speed and efficient resource utilization, which can help improve the overall speed and performance of a WordPress site.

Caching: NGINX includes an HTTP cache that can be used to store frequently accessed WordPress pages and static content, such as images and CSS files. This can significantly reduce the server load and improve the page load time for visitors.

Load Balancing: NGINX can be used as a load balancer to distribute traffic across multiple servers, which can help improve the availability and scalability of WordPress sites.

Security: NGINX includes built-in features for protecting against DDoS attacks and other security threats, which can help keep WordPress sites safe and secure.

Flexibility: NGINX is highly configurable and can be customized to meet the specific needs of a WordPress site. It can be used in combination with other software applications, such as caching plugins and content delivery networks, to further optimize performance and improve the user experience.

How does NGINX differ from Apache?

NGINX and Apache are both popular open-source web server software used to serve web pages and other content on the internet, but they differ in several key ways:

Architecture: Apache uses a multi-process, multi-threaded architecture, whereas NGINX uses an event-driven architecture that is optimized for handling a high volume of concurrent connections with low resource usage.

Performance: NGINX is generally considered to be faster and more efficient than Apache, particularly in handling static content and high volumes of traffic.

Configuration: Apache uses a complex configuration file system, which can be challenging to manage and prone to errors, while NGINX uses a simple and intuitive configuration syntax.

Modules: Apache has a larger number of modules available, covering a wider range of functionality, while NGINX has a smaller number of modules, but they are generally well-designed, optimized, and easier to configure.

Flexibility: NGINX is more flexible and can be used as a reverse proxy, load balancer, and caching server, in addition to its web server capabilities. Apache is primarily a web server and is less suited for these other roles.

In summary, NGINX and Apache have different strengths and weaknesses, and the choice of web server software depends on the specific needs of the application and the preferences of the user.

What are the requirements to run NGINX?

NGINX has relatively low system requirements and can run on a wide range of hardware and software platforms. Here are the basic requirements for running NGINX:

Operating System: NGINX can run on various operating systems, including Linux, FreeBSD, macOS, and Windows. However, it is primarily designed to run on Unix-based systems like Linux.

CPU and RAM: The hardware requirements for NGINX depend on the expected traffic and workload. For small to medium-sized websites, a server with at least 1 CPU core and 512 MB RAM should be sufficient. However, for high-traffic sites or complex applications, more powerful hardware may be required.

Disk Space: NGINX itself does not require much disk space, typically just a few megabytes. However, the disk space requirements will depend on the size and number of web pages and other content that will be served.

Dependencies: NGINX has a few dependencies that must be installed, such as OpenSSL and PCRE (Perl Compatible Regular Expressions) library. These dependencies are typically included in most Linux distributions and can be easily installed using the package manager.

Network Connectivity: NGINX requires network connectivity to serve web pages and other content over the internet. It also requires access to the DNS server to resolve domain names.

In summary, the hardware and software requirements for running NGINX are relatively low, making it a popular choice for a wide range of web applications and services.

What does an example NGINX config look like in code?

Here’s an example NGINX configuration file:


# This is a comment

# Set the user and group that NGINX will run as
user nginx;
worker_processes auto;

# Define the error log file and log level
error_log /var/log/nginx/error.log warn;

http {
    # Set the MIME types for file extensions
    include /etc/nginx/mime.types;

    # Define the default server block
    server {
        # Listen on port 80 for incoming requests
        listen 80;

        # Define the server name and document root
        server_name example.com;
        root /var/www/example.com;

        # Define the default page to serve
        index index.html;

        # Configure caching
        expires 1d;
        add_header Cache-Control "public";

        # Enable gzip compression
        gzip on;
        gzip_types text/plain text/css application/json application/javascript;

        # Define location blocks for specific URL paths
        location / {
            try_files $uri $uri/ /index.html;
        }

        location /api {
            proxy_pass http://localhost:3000;
        }

        # Serve static files directly
        location /static {
            try_files $uri =404;
        }

        # Redirect all other requests to HTTPS
        location / {
            return 301 https://$server_name$request_uri;
        }
    }

    # Define additional server blocks for other domains or subdomains
    server {
        listen 80;
        server_name subdomain.example.com;
        root /var/www/subdomain.example.com;
        index index.html;
        # ...
    }
}

This configuration file sets up an HTTP server to listen on port 80, serves files from the root directory, and defines several location blocks for handling specific URL paths. It also enables caching and gzip compression, and redirects all other requests to HTTPS. Additionally, it defines an additional server block for a subdomain.

Can NGINX run multiple WordPress sites?

Yes, NGINX can be configured to run multiple WordPress sites on a single server. Here’s an example configuration:


server {
    listen 80;
    server_name site1.com www.site1.com;

    root /var/www/site1.com;
    index index.php;

    location / {
        try_files $uri $uri/ /index.php?$args;
    }

    location ~ \.php$ {
        include fastcgi_params;
        fastcgi_pass unix:/var/run/php-fpm.sock;
        fastcgi_index index.php;
        fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
    }
}

server {
    listen 80;
    server_name site2.com www.site2.com;

    root /var/www/site2.com;
    index index.php;

    location / {
        try_files $uri $uri/ /index.php?$args;
    }

    location ~ \.php$ {
        include fastcgi_params;
        fastcgi_pass unix:/var/run/php-fpm.sock;
        fastcgi_index index.php;
        fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
    }
}

This configuration defines two server blocks, each with a separate server_name directive and root directory for the corresponding WordPress site. The location directives handle requests for the site’s URLs and route them to the appropriate index.php file for processing by the PHP FastCGI process manager.

To run multiple WordPress sites, you would need to set up separate databases and configure each WordPress installation to use the correct database and site URL. Additionally, you may need to configure separate PHP-FPM pools to ensure each site has sufficient resources.

What does the file tree look like for NGINX?

The file tree for NGINX can vary depending on the operating system and installation method used. Here’s an example file tree for NGINX installed on a Linux server using a package manager:


/etc/nginx/
├── conf.d/
│   ├── default.conf
│   └── example.conf
├── nginx.conf
├── snippets/
│   ├── fastcgi-php.conf
│   ├── ssl-params.conf
│   └── ...
├── sites-available/
│   ├── example.com
│   ├── subdomain.example.com
│   └── ...
└── sites-enabled/
├── example.com -> ../sites-available/example.com
└── subdomain.example.com -> ../sites-available/subdomain.example.com

/var/log/nginx/
├── access.log
└── error.log

/var/www/
├── example.com/
│ ├── index.html
│ └── ...
└── subdomain.example.com/
├── index.html
└── ...

In this example, the NGINX configuration files are located in the /etc/nginx/ directory. The nginx.conf file is the main configuration file, and it includes additional configuration files located in conf.d/ and sites-enabled/.

The snippets/ directory contains reusable configuration snippets that can be included in other configuration files. The sites-available/ directory contains configuration files for each website, which can be enabled by creating a symbolic link to the corresponding file in the sites-enabled/ directory.

The log files are located in the /var/log/nginx/ directory, and the web files for each website are stored in the /var/www/ directory. In this example, there are separate directories for each website’s files, but in practice, the file structure may be organized differently depending on the needs of the specific setup.

How does ‘site-available’ work with ‘sites-enabled’ ?

In NGINX, the sites-available and sites-enabled directories are used to manage virtual host configurations for different websites.

The sites-available directory contains the configuration files for all the available virtual hosts. These files usually have the .conf extension and contain the configuration details for each website, such as the server name, document root, SSL settings, etc.

By default, none of these virtual host configurations are active. To activate a virtual host configuration, you need to create a symbolic link to the corresponding file in the sites-enabled directory. NGINX will then read the configuration from this file and use it to serve the website.

The sites-enabled directory contains symbolic links to the virtual host configurations that are currently enabled. When you enable a virtual host configuration, NGINX creates a symbolic link to the corresponding configuration file in sites-available. This way, you can easily enable or disable virtual hosts by adding or removing the symbolic links in the sites-enabled directory.

Note that the sites-enabled directory is usually included in the main NGINX configuration file (nginx.conf) using an include directive. For example:


http {
    ...
    include /etc/nginx/sites-enabled/*;
}

This includes all the configuration files in the sites-enabled directory, allowing NGINX to use the virtual host configurations that are currently enabled.

Where are the error logs for NGINX located?

By default, the error logs for NGINX are located in the /var/log/nginx/error.log file. This is the main error log file where NGINX writes all error messages, including startup errors, configuration errors, and runtime errors.

You can view the contents of the error log file using any text editor, or you can use the tail command to view the last few lines of the log in the terminal:


tail -f /var/log/nginx/error.log

This will display the last 10 lines of the error log and continuously update the output as new errors are added to the log file.

Note that the location of the error log file may vary depending on how NGINX was installed and configured. If you’re not sure where the error log file is located, you can check the NGINX configuration file (nginx.conf) for the error_log directive, which specifies the location of the error log file. For example:


error_log /var/log/nginx/error.log;

What are some basic command to start, stop, and restart NGINX?

Here are some basic commands to start, stop, and restart NGINX:

To start NGINX:


sudo systemctl start nginx

To stop NGINX:


sudo systemctl stop nginx

To restart NGINX:


sudo systemctl restart nginx

To check the status of NGINX:


sudo systemctl status nginx

These commands assume that you are using a Linux distribution that uses systemd to manage services, such as Ubuntu or Debian. If you’re using a different distribution, the commands may be different.

Note that you need to run these commands with root or sudo privileges, as NGINX requires root permissions to listen on ports 80 and 443.

How does NGINX caching work?

NGINX caching works by storing frequently accessed content in memory or on disk, so that it can be served quickly to clients without having to regenerate the content each time. When a client requests a resource from the server, NGINX checks its cache to see if it has a cached copy of the resource. If a cached copy exists and is still valid, NGINX serves the cached copy to the client without having to regenerate the content from scratch.

NGINX supports two types of caching: proxy caching and fastcgi caching.

Proxy caching: This type of caching is used when NGINX acts as a reverse proxy to cache the responses from upstream servers. When a client requests a resource, NGINX forwards the request to the upstream server and caches the response. The next time a client requests the same resource, NGINX serves the cached copy directly from memory or disk, without having to forward the request to the upstream server.

FastCGI caching: This type of caching is used when NGINX communicates with PHP-FPM servers using the FastCGI protocol. When a client requests a PHP script, NGINX forwards the request to the PHP-FPM server and caches the response. The next time a client requests the same script, NGINX serves the cached copy directly from memory or disk, without having to forward the request to the PHP-FPM server.

NGINX caching can be configured using the proxy_cache_path or fastcgi_cache_path directives in the NGINX configuration file. These directives specify the location and settings for the cache, such as the size of the cache, the cache key, the cache expiration time, and more.

It’s important to note that caching can improve the performance of your web server, but it can also cause stale content to be served to clients if the cache isn’t properly managed. Therefore, it’s important to configure caching carefully and monitor it regularly to ensure that it’s working as intended.

How can I check NGINX config files for issues?

You can check NGINX config files for issues using the nginx command line tool with the -t or –test option. This option checks the syntax of the config files and reports any errors or warnings.

To check the syntax of the NGINX config files, open a terminal window and run the following command:


nginx -t

If there are no errors, the command will return nginx: configuration file /etc/nginx/nginx.conf syntax is ok and nginx: configuration file /etc/nginx/nginx.conf test is successful.

If there are errors, the command will display an error message that indicates the location and nature of the error in the config file. You should fix the error before restarting NGINX, otherwise NGINX will not start.

In addition to using the nginx command line tool, you can also use external tools to validate your NGINX config files. For example, the nginx-lint tool can check for common mistakes and misconfigurations in NGINX files, while the nginxconfig.io web app can help you generate and validate NGINX config files based on your requirements.

Why do WordPress hosting companies choose NGINX?

WordPress hosting companies choose NGINX for several reasons:

Performance: NGINX is known for its high performance and ability to handle a large number of concurrent connections. This makes it an ideal choice for WordPress hosting companies, who need to serve thousands of requests per second.

Scalability: NGINX can be easily scaled to handle high traffic loads by adding more servers or using load balancing. This makes it a good choice for WordPress hosting companies, who need to accommodate growing numbers of users and traffic.

Reverse proxying: NGINX can be used as a reverse proxy to cache static content and offload dynamic requests to WordPress backend servers. This reduces the load on the backend servers and improves overall performance.

Security: NGINX has built-in security features like SSL/TLS encryption and HTTP/2 support, which can help WordPress hosting companies protect their customers’ websites from attacks.

Flexibility: NGINX is highly configurable and can be customized to meet specific requirements. This makes it a good choice for WordPress hosting companies, who need to provide a wide range of hosting options and features to their customers.

Overall, NGINX is a popular choice for WordPress hosting companies because it offers high performance, scalability, security, flexibility, and ease of use.

How does Let’s Encrypt SSL work with NGINX?

Let’s Encrypt is a free and automated certificate authority that provides SSL/TLS certificates to enable secure HTTPS connections. Integrating Let’s Encrypt SSL with NGINX is a straightforward process that involves the following steps:

Install the Certbot client: Certbot is a tool that simplifies the process of obtaining and installing Let’s Encrypt SSL certificates. You can install Certbot on your server by following the instructions on the Certbot website.

Request a new SSL/TLS certificate: Once Certbot is installed, you can use it to request a new SSL/TLS certificate from Let’s Encrypt. You’ll need to specify the domain name(s) that you want to secure with the SSL/TLS certificate.

Verify domain ownership: Let’s Encrypt requires that you verify that you own the domain(s) that you want to secure with the SSL/TLS certificate. Certbot automates this process by creating a temporary file on your server and checking that it can be accessed from the domain name(s) you specified.

Install the SSL/TLS certificate: Once domain ownership is verified, Certbot will generate the SSL/TLS certificate and store it on your server. You’ll then need to configure NGINX to use the SSL/TLS certificate to secure HTTPS connections.

Configure NGINX for HTTPS: To configure NGINX to use the new SSL/TLS certificate, you’ll need to update your NGINX server block configuration file to include the SSL/TLS certificate and private key. You can use Certbot’s automated configuration tool to update your NGINX configuration file with the necessary settings.

Restart NGINX: Once your NGINX configuration is updated, you’ll need to restart NGINX to apply the changes.

By following these steps, you can easily obtain and install Let’s Encrypt SSL/TLS certificates for your NGINX web server, enabling secure HTTPS connections for your WordPress site.

What’s an example syntax look like to run Let’s Encrypt on an NGINX domain?

Here’s an example syntax for running Let’s Encrypt on an NGINX domain using the Certbot client:


sudo certbot --nginx -d example.com -d www.example.com

In this example, example.com and www.example.com are the domain names for which you want to obtain the SSL/TLS certificates. The –nginx flag indicates that you want to use the NGINX plugin to install the certificates automatically.

When you run this command, Certbot will perform domain ownership verification for each domain specified, and if successful, it will automatically modify your NGINX configuration file to include the SSL/TLS certificates. It will also configure NGINX to redirect all HTTP traffic to HTTPS.

After the SSL/TLS certificates are installed, you can verify that your site is using HTTPS by visiting https://example.com and https://www.example.com in your web browser. If everything is set up correctly, you should see a green padlock icon in the address bar indicating that your connection is secure.

Where can I get started with NGINX?

If you’re new to NGINX, there are several resources you can use to get started:

The official NGINX documentation: This is the best place to start if you want to learn about NGINX. The documentation covers all aspects of NGINX, from installation and configuration to advanced topics like load balancing, caching, and security.

NGINX tutorials: There are many tutorials available online that cover various aspects of NGINX, from basic configuration to advanced features like reverse proxying and load balancing. Some popular websites for NGINX tutorials include DigitalOcean, Linode, and Nginx.com.

NGINX forums and communities: There are several online forums and communities dedicated to NGINX, where you can ask questions and get help from other NGINX users. Some popular forums include the NGINX mailing list and the NGINX community forum.

NGINX books: There are several books available on NGINX, which cover a wide range of topics from basic configuration to advanced use cases. Some popular books include “NGINX High Performance” by Rahul Sharma and “Mastering NGINX” by Dimitri Aivaliotis.

Overall, the best way to get started with NGINX is to start with the official documentation and work your way through tutorials and examples. As you gain more experience with NGINX, you can explore more advanced features and use cases.

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