DMZ Server Installation

A DMZ (Demilitarized Zone) server is a host or service placed within a DMZ network—a subnetwork that acts as a buffer between an organization's internal local-area network (LAN) and untrusted external networks, such as the Internet. The primary purpose of a DMZ server is to handle external-facing services, including web, email, DNS, and FTP servers, thereby adding an extra layer of security to the internal network. By isolating these services in the DMZ, organizations can prevent direct access to their internal LAN, reducing the risk of unauthorized intrusion.

note

This document applies to Ubuntu (v22 and 24) and RedHat (v9.2 and 9.4) OS.

Prerequisites

Internet Connectivity: The system where the DMZ is installed must have access to the Internet.
DMZ Port Access: Ensure that port 8085 is allowed through the firewall.
Checking and Allowing Port 8085 on Ubuntu
Use the following commands to check and configure the firewall:
ufw status
To allow port 8085 through the firewall:
ufw allow 8085
Checking and Allowing Port 8085 on Red Hat
Use the following commands to verify and allow port 8085 through the firewall:
To check the list of currently allowed ports:
sudo firewall-cmd --list-ports
To allow port 8085 on the public zone:
sudo firewall-cmd --zone=public --add-port=8085/tcp