Webmin Deployment Overview¶

Prerequisites¶

The following parameters and conditions are required for the application to function correctly:

Operating System: Debian, Ubuntu, CentOS, Rocky Linux, or AlmaLinux.
Access Rights: root (or a user with sudo privileges).
Ports:
- 10000/tcp — Webmin application internal port.
- 443/tcp — External port for HTTPS access via proxy.

Final FQDN of the panel on hostkey.in domain¶

Parameter	Value
Prefix	`webmin`
Domain	`hostkey.in`
Full Template	`webmin{Server_ID_from_Invapi}.hostkey.in`

File and Directory Structure¶

Main directories used in the system:

/etc/webmin — Webmin configuration files.
/root/nginx — Docker Compose working directory for the proxy server.
/data/nginx/user_conf.d — Directory containing Nginx user configurations.
/data/nginx/nginx-certbot.env — Environment variables file for the Nginx container.

Application Installation Process¶

Installation is performed by adding the official Webmin repository and subsequent installation via the system package manager (apt or yum). After installation, the Webmin self-signed SSL certificate is disabled, and the configuration is set up to operate through a reverse proxy using a public FQDN.

Access Rights and Security¶

The following parameters are configured to ensure security:

Firewall:
- For RHEL-based systems (CentOS/Rocky/AlmaLinux), firewalld is used. Port 10000/tcp is allowed in the public zone.
- For Ubuntu-based systems, ufw is used. Port 10000/tcp is allowed.
Webmin Security: In the /etc/webmin/miniserv.conf file, the ssl parameter is set to 0, as encryption is provided by the Nginx proxy server.

Docker Containers and Execution¶

A containerized proxy server is used to ensure HTTPS operation via Let's Encrypt.

Container: nginx

Image: jonasal/nginx-certbot:latest
Ports: Uses host network mode.
Volumes:
- nginx_secrets:/etc/letsencrypt — Certificate storage.
- /data/nginx/user_conf.d:/etc/nginx/user_conf.d — Nginx configuration files.
Environment Variables:
- [email protected]
Restart Policy: unless-stopped.

Application Update Instructions¶

Updates are performed by updating packages via the system manager or by updating containers:

docker compose pull && docker compose up -d

Or via system package management commands (e.g., apt update && apt upgrade).

Permissions Settings¶

The /root/nginx directory has 0755 permissions.
The compose.yml file in the /root/nginx directory has 0644 permissions, owned by root.

Configuration Files and Data Location¶

Webmin configuration: /etc/webmin/miniserv.conf.
Proxy configuration: /data/nginx/user_conf.d/{prefix}{server_id}.{zone}.conf.

Available Connection Ports¶

Port	Protocol	Purpose
`443`	TCP	HTTPS access to the control panel via domain
`10000`	TCP	Local Webmin port (accessible inside the server)

Starting and Stopping the Application¶

Nginx proxy server management is performed using Docker Compose commands from the /root/nginx directory:

Start:
```
docker compose up -d
```

Reload Nginx Configuration:

docker compose exec -T nginx nginx -s reload

Stop:
```
docker compose down
```

Proxy Servers¶

nginx is used as a proxy server in conjunction with certbot for automatic acquisition and renewal of Let's Encrypt SSL certificates.

Proxy settings include:

Traffic redirection to the local port 127.0.0.1:10000.
Forwarding of Host and X-Forwarded-Proto headers for correct Webmin operation via HTTPS.