Varnish Cache (also referred to as Varnish) is an open source, high-performance HTTP accelerator designed for speeding up web servers. Varnish is the key software in building a high performance web server.
In this post, we will show you how to install and use Varnish Cache 6 LTS as a cache layer to NGINX HTTP server in CentOS 7. This guide should also work on RHEL7.
Requirements:
- A CentOS 7 server with static IP address
Step 1: Install NGINX Web Server on CentOS 7
Start by installing NGINX HTTP server from the GetPageSpeed software repositories using the YUM package manager as follows.
By using GetPageSpeed repository in lieu of other package sources, you can later expand your NGINX with a vast array of useful modules. Using GetPageSpeed repositories requires a subscription.
sudo yum -y install https://extras.getpagespeed.com/release-latest.rpm
sudo yum -y install nginx
When the installation completes, start NGINX service and enable it to start automatically at system boot:
systemctl enable --now nginx
Now modify system firewall rules to permit inbound packets on port 80 using the commands below.
systemctl start firewalld
firewall-cmd --zone=public --permanent --add-service=http
firewall-cmd --reload
Step 2: Install Varnish cache server on CentOS 7
sudo yum -y install yum-utils
sudo yum-config-manager --enable getpagespeed-extras-varnish60
sudo yum -y install varnish
Step 3: Configure NGINX to Work With Varnish Cache
In this step, you need to configure Nginx to work with Varnish Cache. By default Nginx listens on port 80, you need change the default Nginx port to 8080 so it runs behind Varnish caching.
Open the Nginx configuration file /etc/nginx/conf.d/default.conf and find the line listen 80; and change it to listen 8080;.
Then save and close the file.
With all the necessary configurations in place, restart Nginx services as follows.
systemctl restart nginx
Not edit varnish configuration so that it runs on port 80. Open up /etc/varnish/varnish.params and change VARNISH_LISTEN_PORT=6081 to VARNISH_LISTEN_PORT=80
Now enable Varnish at boot time and start Varnish daemon:
systemctl enable varnish
systemctl start varnish
Step 4: Test Varnish Cache on Nginx
Finally, test if Varnish cache is enabled and working with the Nginx service using the cURL command below to view the HTTP header.
curl -I http://localhost
HTTP/1.1 200 OK
Server: nginx/1.12.1
Date: Wed, 04 Oct 2017 21:22:03 GMT
Content-Type: text/html
Content-Length: 612
Last-Modified: Tue, 11 Jul 2017 13:50:19 GMT
ETag: "5964d79b-264"
X-Varnish: 2
Age: 0
Via: 1.1 varnish (Varnish/5.2)
Accept-Ranges: bytes
Connection: keep-alive
Repeating the above command will show that Varnish cached response (note that Age header):
HTTP/1.1 200 OK
Server: nginx/1.12.1
Date: Wed, 04 Oct 2017 21:22:03 GMT
Content-Type: text/html
Content-Length: 612
Last-Modified: Tue, 11 Jul 2017 13:50:19 GMT
ETag: "5964d79b-264"
X-Varnish: 32770 3
Age: 30
Via: 1.1 varnish (Varnish/5.2)
Accept-Ranges: bytes
Connection: keep-alive
We have a lot of Varnish related posts and hope we will find them useful in your Varnish learning.