Advanced IPv4 Subnet Calculator in Python3

Table of Contents

1. Getting Started
2. Installation
3. How it works?
4. SVI Configuration Template
5. Previews

Getting Started

│   main.py
│   read_subnets.py
│   subnetting.py
│   export_subnets.py
│   parse_excel.py
│   svi_generator.py
│   svi.j2
│   subnets.csv
│   requirements.txt
│   README.md
│   .pre-commit-config.yaml
│   .gitignore
│   LICENSE
│
└───assets
        preview.png
        subnets-csv.png
        subnetting-cli.png
        svi-template.png
        svi.png

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Installation

$ git clone https://github.com/Tes3awy/subnetting.git
$ cd subnetting
$ pip install -r requirements.txt --user

OR

1. Download the latest release from Releases.
2. Extract subnetting.zip file.
3. cd into subnetting directory.
4. Run path_to\subnetting> pip install -r requirements.txt --user in terminal.

---

How it works?

Windows

path_to\subnetting> python main.py

macOS or Unix

$ python3 main.py

You will be prompted to enter the name of the CSV file containing input subnets, the gateway, a name for the Excel file to be created. (All inputs have default values).

A subnets.csv file can be found in the repo. This file is an entry point to get started using this program. It's prepopulated with three different subnets. (Class A, B, and C).

- CSV file [subnets.csv]:
- The gateway, first or last IP Address [0/1] [0]:
- Excel file to create [New-Schema.xlsx]:

Voila ✨ You have an Excel file that includes all required data about each subnet.

Please check New-Schema_<TODAYS_DATE>.xlsx in current working directory.

Default behaviors:

1. CIDR notation with no prefix length will be handled as /32.
   - For example, if you enter 10.0.0.1 without a prefix length in the CSV file, the script will handle it like 10.0.0.1/32.

2. The header line Subnets in CIDR Notation within the subnets.csv file is automatically skipped. So, there is no need to manually remove it.

3. The gateway input accepts 0 or 1 ONLY [Defaults to 0]. 0 picks the first IP address of the subnet, while 1 picks the last IP address.

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SVI Configuration Template

Finally, if you have a L3 switch and you want to create SVI interfaces of the created subnets on that switch, you can run:

$ python parse_excel.py --file <EXCEL_FILE_NAME>.xlsx

This Python script will generate a configuration file that includes all VLANs and their SVI interfaces.

NOTE: Make sure you add the VLAN ID and VLAN Name in all the cells in the generated Excel file before running parse_excel.py script. Otherwise, VLAN ID and VLAN Name will be NaN in the generated configuration file.

---

Previews

Terminal Elapsed time is about 9 seconds in here because a CIDR notation like 10.0.0.0/8 is a little bit extensive to process.

CSV File (Input File)

Excel File (Output File)

python parse_excel.py -f <EXCEL_FILE_NAME>.xlsx

SVI Template