How to enable the gzip/deflate in nginx server on Linux or Unix system

I am a new Linux system admin and how can I enable gzip compression on nginx web server for JS/CSS/HTML files?

You need to use the ngx_http_gzip_module module. It compresses all valid HTTP responses (files) using the “gzip” method. This is useful to reduce data transfer size and speed up web pages for static assets such as JavaScript, CSS files and more.

Steps to enable gzip/deflate in nginx server

Edit your nginx.conf file or create a new config file called /etc/nginx/conf.d/static_gzip.conf:
$ sudo vi /etc/nginx/nginx.conf
Add the following in http context:

        # Gzip Settings
        gzip on;
        gzip_disable "msie6";
        gzip_vary on;
        gzip_proxied any;
        gzip_comp_level 6;
        gzip_buffers 16 8k;
        gzip_http_version 1.1;
        gzip_types text/plain text/css application/json application/javascript text/xml application/xml application/xml+rss text/javascript;

Save and close the file. Verify that there are no errors in config file:
$ nginx -t
nginx: the configuration file /etc/nginx/nginx.conf syntax is ok
nginx: configuration file /etc/nginx/nginx.conf test is successful

Restart the nginx server

Type the following command to restart or reload nginx server:
$ sudo service nginx reload
$ sudo systemctl reload nginx
$ sudo /etc/init.d/nginx reload

How do I verify gzip/deflate working or not?

Use the following syntax:
$ curl -I -H 'Accept-Encoding: gzip,deflate' https://your-domain-here/file.css
$ curl -I -H 'Accept-Encoding: gzip,deflate'
$ curl -I -H 'Accept-Encoding: gzip,deflate'

Sample outputs:

HTTP/1.1 200 OK
Server: nginx
Date: Sun, 05 Mar 2017 18:45:31 GMT
Content-Type: text/html; charset=UTF-8
Connection: keep-alive
Vary: Accept-Encoding
X-Whom: l1-com-cyber
Strict-Transport-Security: max-age=15768000; includeSubdomains
Link: ; rel=""
X-Varnish: 1812270 1794298
Age: 475
Via: 1.1 varnish-v4
Front-End-Https: on
Content-Encoding: gzip

For more info see Module ngx_http_gzip_module.

Posted by: SXI ADMIN

The author is the creator of SXI LLC and a seasoned sysadmin, DevOps engineer, and a trainer for the Linux operating system/Unix shell scripting. Get the latest tutorials on SysAdmin, Linux/Unix and open source topics via RSS/XML feed or weekly email newsletter.