Network Subnet Assignment

This script assigns subnets to requested networks based on a base CIDR network. The assigned subnets are non-overlapping and cover the entire base CIDR network.

Requirements

• Python 3.6 or higher
• ipaddress module (included in Python 3)
• json module (included in Python 3)
• argparse module (included in Python 3)
• csv module (included in Python 3)

Usage

python subnetting.py -s BASE_CIDR -j JSON_FILE -l LOCATION_CODE -c COMPANY_NAME

• -s, --base-cidr: the base CIDR network to use (required)
• -j, --json-file: the JSON file containing the network definitions (either JSON or YAML required)
• -y, --yaml-file: the JSON file containing the network definitions (either JSON or YAML required)
• -l, --location-code: a 3-character location code to use in network descriptions (required)
• -c, --company-name: the company name to use in network descriptions (required)
• -o, --output-csv: save the output as csv (optional)

JSON File Format

The JSON file should be an array of network objects, where each object has the following properties:

• name: the name of the network
• cidr: the size of the network in CIDR notation (e.g. 22)
• vid: the VLAN ID to use for the network

Example JSON file:

[
    {
        "name": "server",
        "cidr": 22,
        "vid": 2000
    },
    {
        "name": "clients",
        "cidr": 22,
        "vid": 2010
    },
    {
        "name": "guest-wifi",
        "cidr": 23,
        "vid": 2021
    }
]

YAML File Format

The JSON/YAML file should be an array of network objects, where each object has the following properties:

• name: the name of the network
• cidr: the size of the network in CIDR notation (e.g. 22)
• vid: the VLAN ID to use for the network

Example YAML file:

- name: server
  cidr: 22
  vid: 2000
- name: clients
  cidr: 22
  vid: 2010
- name: guest-wifi
  cidr: 23
  vid: 2021

Output

The script outputs the assigned subnets for each network in the following format:

192.0.1.0/22 clients (My Company - server)
192.0.2.0/22 server (My Company - clients)
192.0.3.0/23 guest (My Company - guest-wifi)

The network description includes the company name and location code.

If provided, the output is saved to a csv file.

Example

# Assign subnets of the base network 10.10.0.0/19
subnetting.py -s 192.0.2.0/24 -j net_definitions.json -l MUC -c MyCompany

# Assign subnets of the base network 10.10.0.0/19 and save the output to the csv file
subnetting.py -s 192.0.2.0/24 -j net_definitions.json -l MUC -c MyCompany -o subnets.csv

License

This project is licensed under the terms of the MIT license.