ansible-role-ip_forwarding

This Ansible role enables IP forwarding and configures NAT using iptables.

Requirements

• An Ubuntu-based system (tested on Ubuntu).
• Ansible installed.
• vpc_network_prefixes variable defined with one or more VPC network addresses.

Role Variables

• vpc_network_prefixes: A list of VPC network addresses to NAT (e.g., ["10.0.0.0/24"]). The role configures a masquerade rule for each entry.

Dependencies

This role has no dependencies.

Example Playbook

- hosts: your_hosts
  become: true
  vars:
    vpc_network_prefixes:        # replace with your VPC network(s)
      - "10.0.0.0/24"
  roles:
    - brett-buskirk.ip_forwarding

Installation

You can install this role using Ansible Galaxy:

ansible-galaxy install brett-buskirk.ip_forwarding

Or you can include it in your requirements.yml file:

---
roles:
  - name: brett-buskirk.ip_forwarding
    src: https://github.com/brett-buskirk/ansible-role-ip_forwarding
    version: main # or a specific tag

Then install it using:

ansible-galaxy install -r requirements.yml

Role Tasks

This role performs the following tasks:

• Install iptables-persistent: Installs the iptables-persistent package to save iptables rules across reboots.
• Enable IP Forwarding: Enables IP forwarding by setting net.ipv4.ip_forward to 1 in sysctl.
• Persist IP Forwarding: Uncomment the net.ipv4.ip_forward line in /etc/sysctl.conf to make the IP forwarding change permanent.
• Configure NAT (Network Address Translation): Configures iptables to perform NAT for traffic originating from the specified VPC networks (vpc_network_prefixes) to the public interface (eth0).
• Persist NAT Configuration: Saves the iptables rules to /etc/iptables/rules.v4 to ensure the NAT configuration persists across reboots.

Usage

Include the role in your playbook as shown in the "Example Playbook" section. The role will automatically install the necessary packages on the target host.

License

MIT

Author Information

This role was created by Brett Buskirk.

Galaxy Tags

networking, iptables, nat, ip_forwarding