How to Setup Nginx as Reverse Proxy On Ubuntu Server
Nginx is a free, open-source, lightweight, and high-performance web server around the world. It is specially designed to address the performance limitations of Apache web servers. It uses an event-driven architecture and can handle multiple requests within one thread. Generally, Nginx is often used as a reverse proxy or caching service. Nginx reverse proxy is a proxy service that directs client requests to one or more backend servers. You can use Nginx reverse proxy for various protocols such as HTTP, HTTPS, TCP, UDP, SMTP, IMAP, and POP3.
Both Apache and Nginx web servers are most popular on the internet. The Apache Web Server is known for its power while the Nginx is known for its speed. Apache is designed to serve dynamic content while the Nginx is better for serving static content. Combining both servers will dramatically increase the performance of your website.
Features of Nginx Reverse Proxy
- Load Balancing – A reverse proxy server sits in front of multiple backend servers and distributes clients requests across multiple servers. This will improve the website speed and capacity utilization. If one server goes down, the load balancer will redirects traffic to another server.
- Security – A reverse proxy server provides an additional defense against security attacks by hiding the identity of backend servers.
- Performance – A reverse proxy server can cache the common content and compress the inbound and outbound data, which will drastically improve the connection speed between client and server.
In this guide, we will explain how to configure an Nginx reverse proxy in front of an Apache webserver on Ubuntu.
Getting Started
Before starting, you will need to update your system’s package cache to the latest version. You can update it using the following command:
apt-get update -y
Once your system is updated, install some basic packages using the following command:
apt-get install wget curl gnupg2 nano -y
Once you are done, you can proceed to install the Apache webserver.
Installing and Configuring Apache
Before starting, you will need to install and configure the Apache web server as a backend server running on port 8080.
First, install the Apache webserver package using the command below:
apt-get install apache2 libapache2-mod-php -y
After installing Apache, you will need to change the Apache default port from 80 to 8080. You can do it by editing /etc/apache2/ports.conf file:
nano /etc/apache2/ports.conf
Find the following line:
Listen 80
And, replaced it with the following line:
Listen 8080
Save and close the file then you will also need to disable the Apache default virtual host file which is configured to listen on port 80.
a2dissite 000-default
Next, create a new Apache virtual host configuration file that listens on port 8080.
nano /etc/apache2/sites-available/example.conf
Add the following lines:
<VirtualHost *:8080>
ServerAdmin admin@example.com
DocumentRoot /var/www/html
DirectoryIndex index.html
ErrorLog ${APACHE_LOG_DIR}/error.log
CustomLog ${APACHE_LOG_DIR}/access.log combined
</VirtualHost>
Save and close the file when you are finished.
- ServerAdmin – Define the email address of the server administrator.
- DocumentRoot – Path of the Apache default root directory.
- DirectoryIndex – Define the default index file that will load when someone accesses the Apache.
- ErrorLog – Path of the Apache server error log.
- CustomLog – Path of the Apache server access log.
Now, activate the Apache default virtual host file using the command below:
a2ensite example.conf
Finally, reload the Apache service to apply the configuration changes:
systemctl reload apache2
You can also check the status of the Apache service using the following command:
systemctl status apache2
If everything is fine, you should see the following output:
● apache2.service - The Apache HTTP Server
Loaded: loaded (/lib/systemd/system/apache2.service; enabled; vendor preset: enabled)
Active: active (running) since Tue 2021-09-06 10:16:28 UTC; 2s ago
Docs: https://httpd.apache.org/docs/2.4/
Process: 45027 ExecStart=/usr/sbin/apachectl start (code=exited, status=0/SUCCESS)
Main PID: 45031 (apache2)
Tasks: 6 (limit: 2341)
Memory: 14.6M
CPU: 89ms
CGroup: /system.slice/apache2.service
├─45031 /usr/sbin/apache2 -k start
├─45032 /usr/sbin/apache2 -k start
├─45033 /usr/sbin/apache2 -k start
├─45034 /usr/sbin/apache2 -k start
├─45035 /usr/sbin/apache2 -k start
└─45036 /usr/sbin/apache2 -k start
Aug 17 10:16:28 debian systemd[1]: Starting The Apache HTTP Server...
Now, verify the Apache listening port using the following command:
ss -antpl | grep -i apache2
Sample output:
LISTEN 0 511 *:8080 *:* users:(("apache2",pid=10773,fd=4),("apache2",pid=10772,fd=4),("apache2",pid=10771,fd=4),("apache2",pid=10770,fd=4),("apache2",pid=10769,fd=4),("apache2",pid=10768,fd=4))
Configuring Firewall for Apache and Nginx
If the UFW firewall is installed and configured in your server then you will need to allow ports 22, 80, 443 and 8080 through the firewall.
Run the following command to allow all ports:
ufw allow 22
ufw allow 8080
ufw allow http
ufw allow https
Next, reload the UFW firewall using the following command:
ufw disable
ufw enable
Next, verify the status of the UFW firewall rules using the following command:
ufw status
Sample output:
Status: active
To Action From
-- ------ ----
22/tcp ALLOW Anywhere
80/tcp ALLOW Anywhere
443/tcp ALLOW Anywhere
8080 ALLOW Anywhere
22/tcp (v6) ALLOW Anywhere (v6)
80/tcp (v6) ALLOW Anywhere (v6)
443/tcp (v6) ALLOW Anywhere (v6)
8080 (v6) ALLOW Anywhere (v6)
Verifying Apache Backend Server
To verify the Apache web server, open your web browser and type the URL http://your-server-ip:8080 in the address bar. You should see the Apache default page in the following screen:
Installing and Configuring Nginx as a Reverse Proxy for Apache
Now, you will need to install the Nginx web server and configure it as a front-end proxy server for the Apache webserver.
First, install the Nginx package using the following command:
apt-get install nginx -y
After the successful installation, remove the Nginx default virtual host configuration file using the command below:
rm -rf /etc/nginx/sites-enabled/default
Next, create a new Nginx virtual host configuration file to pass the incoming requests to the Apache backend server:
nano /etc/nginx/conf.d/proxy.conf
Add the following lines:
server {
listen 80;
server_name proxy.example.com;
location / {
proxy_pass http://your_server_ip:8080;
proxy_set_header Host $host;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_set_header X-Forwarded-Proto $scheme;
}
}
Save and close the file then verify the Nginx for any configuration error using the following command:
nginx -t
Sample output:
nginx: the configuration file /etc/nginx/nginx.conf syntax is ok
nginx: configuration file /etc/nginx/nginx.conf test is successful
Next, reload the Nginx service to apply the configuration changes:
systemctl reload nginx
You can check the status of the Nginx service using the following command:
systemctl status nginx
If everything is fine, you should see the following output:
● nginx.service - A high performance web server and a reverse proxy server
Loaded: loaded (/lib/systemd/system/nginx.service; enabled; vendor preset: enabled)
Active: active (running) since Sat 2021-09-06 07:33:12 UTC; 5s ago
Docs: man:nginx(8)
Process: 17460 ExecStartPre=/usr/sbin/nginx -t -q -g daemon on; master_process on; (code=exited, status=0/SUCCESS)
Process: 17461 ExecStart=/usr/sbin/nginx -g daemon on; master_process on; (code=exited, status=0/SUCCESS)
Main PID: 17462 (nginx)
Tasks: 2 (limit: 2341)
Memory: 2.4M
CPU: 50ms
CGroup: /system.slice/nginx.service
├─17462 nginx: master process /usr/sbin/nginx -g daemon on; master_process on;
└─17463 nginx: worker process
Sep 04 07:33:12 ubuntu systemd[1]: Starting A high performance web server and a reverse proxy server...
Sep 04 07:33:12 ubuntu systemd[1]: nginx.service: Failed to parse PID from file /run/nginx.pid: Invalid argument
Sep 04 07:33:12 ubuntu systemd[1]: Started A high performance web server and a reverse proxy server.
Verify Nginx Front-End Server
At this point, Nginx has been configured as a front-end server for Apache. Now it’s time to verify whether the Nginx passes the requests to the Apache webserver.
Open the command-line terminal interface and run the following command to test the Nginx proxy:
curl -I http://proxy.example.com
If everything is fine, you should get the following output:
HTTP/1.1 200 OK
Server: nginx/1.18.0 (Ubuntu)
Date: Thu, 02 Sep 2021 15:27:04 GMT
Content-Type: text/html
Content-Length: 10918
Connection: keep-alive
Last-Modified: Thu, 02 Sep 2021 15:18:16 GMT
ETag: "2aa6-5cb04b131c101"
Accept-Ranges: bytes
Vary: Accept-Encoding
You can also test the Nginx proxy using the URL http://proxy.example.com in your web browser. If everything is fine, you should see the Apache backend server default page as shown below:
Conclusion
In this guide, we explained how to install and configure Apache as a backend server on port 8080. Then, we explained how to configure Nginx as a reverse proxy to pass the client’s request to the Apache backend server. I hope you have now enough understanding of how Nginx reverse proxy works.
