Varnish Cache is a free and open-source reverse-proxy HTTP accelerator for websites and APIs. It can be installed as a reverse proxy in front of any web server running on HTTP. It sits between the web server and browser and saves web pages, cookies and other data into memory. This cache will be used to serve all future requests for exactly similar content. This will increase the web application load and improve the web server performance by 300+ times.
In this tutorial, we will set up Nginx server as a backend server and configure it to listen on port 8080, then configure Varnish cache to listen on default HTTP port 80.
Prerequisites
- A server running CentOS 8.
- A root password is configured the server.
Install and Configure Nginx Web Server
First, you will need to install the Nginx web server in your system. You can install it with the following command:
dnf install nginx -y
Once installed, start the Nginx service and enable it to start at system reboot with the following command:
systemctl start nginx
systemctl enable nginx
By default, the Nginx is listening on port 80. So you will need to configure Nginx to listen on port 80. You can configure it by editing Nginx default configuration file:
nano /etc/nginx/nginx.conf
Find the following lines:
listen 80 default_server; listen [::]:80 default_server;
And, replace them with the following lines:
listen 8080 default_server; listen [::]:8080 default_server;
Save and close the file when you are finished. Then, restart the Nginx service to apply the changes:
systemctl restart nginx
At this point, the Nginx web server is installed and listening on port 8080. You can check it using the following command:
netstat -tpln | grep 8080
You should get the following output:
tcp 0 0 0.0.0.0:8080 0.0.0.0:* LISTEN 30367/nginx: master tcp6 0 0 :::8080 :::* LISTEN 30367/nginx: master
Install Varnish Cache
By default, Varnish package is available in the CentOS 8 default repository. You can install it by just running the following command:
dnf module install varnish
Once installed, start the Varnish service with the following command:
systemctl start varnish
You can also verify the installed version of Varnish cache with the following command:
varnishd -V
You should see the following output:
varnishd (varnish-6.0.2 revision 0458b54db26cfbea79af45ca5c4767c7c2925a91) Copyright (c) 2006 Verdens Gang AS Copyright (c) 2006-2018 Varnish Software AS
Configure Varnish for Nginx
Next, you will need to configure varnish to run on port 80 to receive HTTP requests from clients. You can configure it by editing Varnish default configuration file:
systemctl edit --full varnish
Find the following line:
ExecStart=/usr/sbin/varnishd -a :6081 -f /etc/varnish/default.vcl -s malloc,256m
And, replace it with the following line:
ExecStart=/usr/sbin/varnishd -a :80 -f /etc/varnish/default.vcl -s malloc,256m
Save and close the file when you are finished.
Next, you will need to define the backend server for Varnish. You can do it by editing Varnish main configuration file /etc/varnish/default.vcl:
nano /etc/varnish/default.vcl
Change the following lines:
backend myserver { .host = "127.0.0.1"; .port = "8080"; }
Save and close the file when you are finished. Then, reload the systemd daemon with the following command:
systemctl daemon-reload
Next, restart the Varnish service and enable it to start at system reboot with the following command:
systemctl restart varnish
systemcl enable varnish
You can also verify the status of the Varnish with the following command:
systemctl status varnish
You should get the following output:
? varnish.service - Varnish Cache, a high-performance HTTP accelerator Loaded: loaded (/etc/systemd/system/varnish.service; disabled; vendor preset: disabled) Active: active (running) since Sat 2020-08-29 09:36:58 EDT; 12s ago Process: 30421 ExecStart=/usr/sbin/varnishd -a :80 -f /etc/varnish/default.vcl -s malloc,256m (code=exited, status=0/SUCCESS) Main PID: 30424 (varnishd) Tasks: 217 Memory: 91.8M CGroup: /system.slice/varnish.service ??30424 /usr/sbin/varnishd -a :80 -f /etc/varnish/default.vcl -s malloc,256m ??30434 /usr/sbin/varnishd -a :80 -f /etc/varnish/default.vcl -s malloc,256m Aug 29 09:36:57 centos8 systemd[1]: Starting Varnish Cache, a high-performance HTTP accelerator... Aug 29 09:36:58 centos8 varnishd[30421]: Debug: Version: varnish-6.0.2 revision 0458b54db26cfbea79af45ca5c4767c7c2925a91 Aug 29 09:36:58 centos8 varnishd[30421]: Debug: Platform: Linux,4.18.0-193.6.3.el8_2.x86_64,x86_64,-junix,-smalloc,-sdefault,-hcritbit Aug 29 09:36:58 centos8 varnishd[30424]: Version: varnish-6.0.2 revision 0458b54db26cfbea79af45ca5c4767c7c2925a91 Aug 29 09:36:58 centos8 varnishd[30424]: Platform: Linux,4.18.0-193.6.3.el8_2.x86_64,x86_64,-junix,-smalloc,-sdefault,-hcritbit Aug 29 09:36:58 centos8 varnishd[30421]: Debug: Child (30434) Started Aug 29 09:36:58 centos8 varnishd[30424]: Child (30434) Started Aug 29 09:36:58 centos8 varnishd[30424]: Child (30434) said Child starts Aug 29 09:36:58 centos8 systemd[1]: Started Varnish Cache, a high-performance HTTP accelerator.
You can now verify listening port of Nginx and Varnish with the following command:
netstat -tpln | grep 80
You should see the following output:
tcp 0 0 0.0.0.0:80 0.0.0.0:* LISTEN 30424/varnishd tcp 0 0 0.0.0.0:8080 0.0.0.0:* LISTEN 30367/nginx: master tcp6 0 0 :::80 :::* LISTEN 30424/varnishd tcp6 0 0 :::8080 :::* LISTEN 30367/nginx: master
Configure SELinux and Firewall
By default, SELinux is enable in CentOS 8. So you will need to configure SELinux for Varnish. You can configure it with the following command:
setsebool -P httpd_can_network_connect 1
Next, you will need to allow port 80 through firewalld. You can do it with the following command:
firewall-cmd --permanent --zone public --add-port 80/tcp
firewall-cmd --reload
Once you are finished, you can proceed to the next step.
Test Varnish Cache
At this point, Varnish cache is installed and configured with Nginx web server. Now, its time to test whether Varnish cache is works or not.
You can test it using the curl command as shown below:
curl -I http://localhost
You should see the following output:
HTTP/1.1 200 OK Server: nginx/1.14.1 Date: Sat, 29 Aug 2020 13:53:44 GMT Content-Type: text/html; charset=UTF-8 X-Powered-By: PHP/7.2.24 X-Varnish: 32800 Age: 0 Via: 1.1 varnish (Varnish/6.0) Accept-Ranges: bytes Connection: keep-alive
Conclusion
Congratulations! you have successfully installed Varnish Cache with Nginx on CentOS 8. I hope you can also configure Varnish cache with Apache web server easily. Feel free to ask me if you have any questions.
Đăng ký liền tay Nhận Ngay Bài Mới
Subscribe ngay
Cám ơn bạn đã đăng ký !
Lỗi đăng ký !
Add Comment