How to Install Caddy Webserver on Ubuntu 24.04

Introduction

Caddy is an open-source web server that supports static and modern web applications using predefined configuration rules with automatic HTTPS enabled for all linked domain names. Written in GO, Caddy offers user-friendly configuration directives that enable you to either use it as a web server, reverse proxy, or load balancer to serve web applications on your server.

This article explains how to install the Caddy web server on Ubuntu 24.04 and securely serve web applications on the server.

Prerequisites

Before you begin:

• Deploy an Ubuntu 24.04 server instance on Vultr.

• Create a domain name A record pointing to the server IP address.

• Access the server using SSH.

• Create a non-root account with sudo privileges and switch to the account.

Install Caddy

Caddy is not available in the default Ubuntu 24.04 APT repositories but can be installed from source files or by adding the latest repository information on your server. Follow the steps below to download the latest Caddy repository information and install the application on your server.

1. Add the latest Caddy GPG Key to your server.

   CONSOLE

   Copy

   $ curl -1sLf 'https://dl.cloudsmith.io/public/caddy/stable/gpg.key' | sudo gpg --dearmor -o /usr/share/keyrings/caddy-stable-archive-keyring.gpg

   Explain Code

   Powered by Vultr AgentBeta

2. Add the Caddy repository to your APT sources.

   CONSOLE

   Copy

   $ curl -1sLf 'https://dl.cloudsmith.io/public/caddy/stable/debian.deb.txt' | sudo tee /etc/apt/sources.list.d/caddy-stable.list

   Explain Code

   Powered by Vultr AgentBeta

3. Update the server package index.

   CONSOLE

   Copy

   $ sudo apt update

   Explain Code

   Powered by Vultr AgentBeta

4. Install Caddy.

   CONSOLE

   Copy

   $ sudo apt install caddy

   Explain Code

   Powered by Vultr AgentBeta

5. View the installed Caddy version to verify that the installation is successful.

   CONSOLE

   Copy

   $ caddy -v

   Explain Code

   Powered by Vultr AgentBeta

   Output:

   v2.8.4 h1:q3pe0wpBj1OcHFZ3n/1nl4V4bxBrYoSoab7rL9BMYNk=

6. Allow incoming connections to the HTTP port 80 through the firewall.

   CONSOLE

   Copy

   $ sudo ufw allow 80

   Explain Code

   Powered by Vultr AgentBeta

7. Restart the firewall to apply changes.

   CONSOLE

   Copy

   $ sudo ufw reload

   Explain Code

   Powered by Vultr AgentBeta

8. Access your server IP to test access to the Caddy web server.

   http://SERVER-IP

   Confirm that the default Caddy webpage displays in your browser.

   

Manage the Caddy System Service

1. Enable Caddy to start at boot time.

   CONSOLE

   Copy

   $ sudo systemctl enable caddy

   Explain Code

   Powered by Vultr AgentBeta

2. Start the Caddy web server.

   CONSOLE

   Copy

   $ sudo systemctl start caddy

   Explain Code

   Powered by Vultr AgentBeta

3. View the Caddy system service status to verify that the application is running.

   CONSOLE

   Copy

   $ sudo systemctl status caddy

   Explain Code

   Powered by Vultr AgentBeta

   Output:

   ● caddy.service - Caddy
        Loaded: loaded (/usr/lib/systemd/system/caddy.service; enabled; preset: enabled)
        Active: active (running) since Mon 2024-06-10 14:46:16 UTC; 8min ago
          Docs: https://caddyserver.com/docs/
      Main PID: 30024 (caddy)
         Tasks: 7 (limit: 1061)
        Memory: 11.7M (peak: 13.9M)
           CPU: 138ms
        CGroup: /system.slice/caddy.service
                └─30024 /usr/bin/caddy run --environ --config /etc/caddy/Caddyfile

Create a Caddy Virtual Host

Caddy stores configuration files in the /etc/caddy directory by default and supports Caddyfile configurations from any location on your server. Follow the steps below to create a new Caddy virtual host to serve web application files from the /var/www/example.com directory on your server.

1. Create the /var/www/example.com web application files directory.

   CONSOLE

   Copy

   $ sudo mkdir -p /var/www/example.com

   Explain Code

   Powered by Vultr AgentBeta

2. Create a new HTML application file index.html.

   CONSOLE

   Copy

   $ sudo nano /var/www/example.com/index.html

   Explain Code

   Powered by Vultr AgentBeta

3. Add the following code to the file.

   HTML

   Copy

   <html>
   <head>
       <title>Greetings from Vultr!</title>
   </head>
   <body>
       <br>
       <br>
       <br>
       <h1 align="center">Hello World!, Greetings from Vultr</h1>
   </body>
   </html>

   Explain Code

   Powered by Vultr AgentBeta

   Save and close the file.

4. Switch to the Caddy configuration files directory.

   CONSOLE

   Copy

   $ cd /etc/caddy/

   Explain Code

   Powered by Vultr AgentBeta

5. Back up the default Caddyfile configuration.

   CONSOLE

   Copy

   $ sudo mv Caddyfile Caddyfile.default

   Explain Code

   Powered by Vultr AgentBeta

6. Create a new Caddyfile configuration.

   CONSOLE

   Copy

   $ sudo nano Caddyfile

   Explain Code

   Powered by Vultr AgentBeta

7. Add the following configurations to the file.

   INI

   Copy

   example.com {
           tls admin@example.com
           root * /var/www/example.com
           file_server {
               index index.html
           }
           log {
           output file /var/log/caddy/example.log
           format console
           }
   }

   Explain Code

   Powered by Vultr AgentBeta

   Save and exit the file.

   The above Caddy configuration creates a new virtual host using your domain example.com. Within the configuration:

   • example.com: Creates a new virtual host profile using your IP address or domain.
   • tls: Specifies the email address to associate with Let's Encrypt SSL certificate generation requests.
   • root: Sets the virtual host web application files directory.
   • file_server: Enables the web application file server. Within the directive, index specifies the default file to serve when your domain is accessed.
   • log: Enables logging of access and error details to a specific file such as /var/log/caddy/example.log.

8. Test the Caddy configuration for errors.

   CONSOLE

   Copy

   $ caddy validate

   Explain Code

   Powered by Vultr AgentBeta

   Output:

   ...........
   2024/06/1 15:19:11.478 INFO    tls.cache.maintenance   started background certificate maintenance      {"cache": "0xc0000e5300"}
   2024/06/1 15:19:11.478 INFO    tls.cache.maintenance   stopped background certificate maintenance      {"cache": "0xc0000e5300"}
   Valid configuration

9. Reload the Caddy web server to apply your configuration changes.

   CONSOLE

   Copy

   $ sudo caddy reload

   Explain Code

   Powered by Vultr AgentBeta

Secure the Caddy Web Server

Caddy uses automatic HTTPS to secure all connections using SSL certificates on virtual host profiles with valid domains on your server. Follow the steps below to secure the Caddy web server by limiting access to the Caddyfile configurations from unintended or unauthorized user changes.

1. Grant the Caddy user full privileges to the /etc/caddy directory.

   CONSOLE

   Copy

   $ sudo chown -R caddy:caddy /etc/caddy

   Explain Code

   Powered by Vultr AgentBeta

2. Grant the Caddy user read and write permissions to the Caddyfile while disabling access for other system users.

   CONSOLE

   Copy

   $ sudo chmod 660 /etc/caddy/Caddyfile

   Explain Code

   Powered by Vultr AgentBeta

3. Long list the /etc/caddy directory to verify the permission changes.

   CONSOLE

   Copy

   $ ls -l /etc/caddy/

   Explain Code

   Powered by Vultr AgentBeta

   Output:

   total 8
   -rw-rw---- 1 caddy caddy 168 Jun 2 15:20 Caddyfile
   -rw-r--r-- 1 caddy caddy 769 Jun  2 12:07 Caddyfle.default

Set Up Firewall Rules

Caddy uses the HTTP port 80 and HTTPS port 443 depending on your Caddyfile configurations to serve files on the server. Follow the steps below to allow all the Caddy ports through the firewall and enable network connections to the web server.

1. View the UFW status and verify that it's active.

   CONSOLE

   Copy

   $ sudo ufw status

   Explain Code

   Powered by Vultr AgentBeta

   If the status is inactive, allow the SSH port 22 and enable UFW.

   CONSOLE

   Copy

   $ sudo ufw allow 22 && sudo ufw enable

   Explain Code

   Powered by Vultr AgentBeta

2. Allow incoming connections to the HTTP port 80.

   CONSOLE

   Copy

   $ sudo ufw allow 80

   Explain Code

   Powered by Vultr AgentBeta

3. Allow incoming connections to the HTTPS port 443.

   CONSOLE

   Copy

   $ sudo ufw allow 443

   Explain Code

   Powered by Vultr AgentBeta

4. Reload the firewall to apply changes

   CONSOLE

   Copy

   $ sudo ufw reload

   Explain Code

   Powered by Vultr AgentBeta

5. Access your domain using a browser such as Chrome to verify that Caddy serves your virtual host web application fils.

   https://example.com

   If you receive a connection error, view the Caddy configuration logs to verify the error details.

   

Conclusion

You have installed the Caddy web server on an Ubuntu 24.04 server and set up a virtual host profile to serve web application files on the server. Visit the Caddy documentation for more information and configuration options.