AC Hosting Environment

AC Hosting Environment Documentation
  • 1 Release Notes
    • 1.1 End-Of-Life (EOL) Notice
    • 1.2 Support Policy
    • 1.3 Differences to CentOS
  • 2 Deployment
    • 2.1 Prerequisites
    • 2.2 Preparing to Install
    • 2.3 Installation
    • 2.4 Post Installation Steps
  • 3 AC Tools
    • 3.1 AC Configure Syslog
      • 3.1.1 Introduction
      • 3.1.2 Un/Installation
      • 3.1.3 Usage
    • 3.2 AC Firewall
      • 3.2.1 Introduction
      • 3.2.2 Un/Installation
      • 3.2.3 Usage
    • 3.3 AC Integrity
      • 3.3.1 Introduction
      • 3.3.2 Un/Installation
      • 3.3.3 Usage
      • 3.3.4 Integration Tips
    • 3.4 Make Bash Installer
      • 3.4.1 Introduction
      • 3.4.2 Un/Installation
      • 3.4.3 Usage
    • 3.5 AC X509 Authority
      • 3.5.1 Introduction
      • 3.5.2 Un/Installation
      • 3.5.3 Command Reference
      • 3.5.4 Certificates For Beginners
      • 3.5.5 CA Management
      • 3.5.6 Server, Client, and User Certificate Management
      • 3.5.7 Reporting Commands
      • 3.5.8 Troubleshooting

3.2.1 Introduction

September 13th, 2025

AC Firewall is user friendly abstraction layer to iptables, which is itself an abstraction layer to the Netfilter kernel module. The main goal of AC Firewall is to provide the following:

  • A simple text file based firewall configuration.
  • Easy interface for application to update the firewall rules as needed.

This runs as the systemd service ac_firewall.service with restrictive inbound connectivity.

A firewall causes resource consumption relative to the level of traffic it filters. Any high load enterprise-class system should run with the local firewall disabled. Hardware firewall appliances are the recommended approach for high traffic use cases.

The goal is not to replicate the full and powerful functionality of iptables, but instead to offer the most common subset of features required by 99.9% of uses cases in the simplest way possible. As such, the scaled back feature set includes the following:

  • General interface open or blocked.
  • Outbound traffic to a port or range of ports
  • Inbound traffic to a port or range of ports
  • Inbound traffic restricted by source IP address
  • Port Address Translation (PAT)
  • Logging of blocked packets
  • Ping (ICMP) allowed or blocked

AC Firewall is created and maintained by Joey Dobias.

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