https://github.com/giovanni-iannaccone/subnethero
subnetting tables generator 🦸♂️
https://github.com/giovanni-iannaccone/subnethero
c cli-tool csv flat flsm ipv4 network subnet subnet-calculator subnetter subnetting vlsm
Last synced: 4 months ago
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subnetting tables generator 🦸♂️
- Host: GitHub
- URL: https://github.com/giovanni-iannaccone/subnethero
- Owner: giovanni-iannaccone
- License: gpl-3.0
- Created: 2025-06-28T16:27:43.000Z (4 months ago)
- Default Branch: main
- Last Pushed: 2025-07-02T09:16:56.000Z (4 months ago)
- Last Synced: 2025-07-02T10:22:51.335Z (4 months ago)
- Topics: c, cli-tool, csv, flat, flsm, ipv4, network, subnet, subnet-calculator, subnetter, subnetting, vlsm
- Language: C
- Homepage:
- Size: 46.9 KB
- Stars: 0
- Watchers: 0
- Forks: 0
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
- Contributing: CONTRIBUTING.md
- License: LICENSE
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# 🦸♂️ Subnethero
Subnethero is a powerful C-based command-line tool designed to help network administrators and IT professionals generate subnetting tables and manage IP ranges for different network configurations. Whether you're using a flat approach, FLSM (Fixed-Length Subnet Mask), or VLSM (Variable-Length Subnet Mask), this tool will streamline the process of subnetting and ensure you get precise network breakdowns.
## 🧮 Features
- Multiple subnetting approaches (flat, flsm, vlsm)
- Simple command-line interface
- Displays subnet information in a clear tabular format
- Generates subnetting tables with efficient algorithm
- Save the output to a csv file
- Parse csv to get network configuration
- IP lookup to know which subnet owns an IP
## 📡 Installation
1. Download subnethero with git
```sh
git clone https://github.com/giovanni-iannaccone/subnethero
cd subnethero
```
2. Compile it using make
```sh
make all
```
## 💡 Command-Line Usage
```
subnethero v1.0
Usage:
subnethero [-t | -f | -v] -c cidr -i ip -s n {n devices for each network}
Options:
-t | --flat use the flat approach
-f | --flsm use the flsm approach
-v | --vlsm use the vlsm approach
-i | --ip specify the IP of the base network
-c | --cidr the CIDR of the original network
-s | --subs number of subnetworks (followed by n devices for each network)
Optional:
-p | --input read network configuration from a csv file
-o | --output copy the output into csv file
-l | --lookup find which subnet owns an ip
Example: subnethero -v -c 24 -i 192.168.1.0 -s 3 64 5 15
```
### Parameters:
- `-t` | `--flat`
This option uses a flat approach to subnetting, dividing the network into one big subnet.
- `-f` | `--flsm`
This option applies the Fixed-Length Subnet Mask method, creating subnets of the same size based on the given number of devices.
- `-v` | `--vlsm`
This option uses the Variable-Length Subnet Mask method, where each subnet can vary in size according to the number of devices specified.
- `-i` | `--ip`
Enter the starting IP address of the network you want to subnet (e.g., 192.168.1.0).
- `-c` | `--cidr`
Specify the CIDR notation for the original network (e.g., /24).
- `-s` | `--subs`
Define the number of subnets you need, followed by the number of devices in each subnet. The tool will calculate the necessary subnet masks.
- `-p` | `--input`
Read network configuration from a csv file and do calculations on that configuration (e.g., `lookup`).
- `-o` | `--output`
Copy the output to a csv file (e.g., output.csv), don't specify anything to print the table to stdout.
- `-l` | `--lookup`
To determine which subnet a specific IP address belongs to, simply add the `-l IP` flag at the end of your command.
## 🛸 Output Format
For each subnet, the output will generate the following columns:
| IP | CIDR | Broadcast | Start | End | Free from | to |
|---------------|------|---------------|---------------|---------------|----------------|---------------|
| 192.168.1.0 | /26 | 192.168.1.63 | 192.168.1.1 | 192.168.1.32 | 192.168.1.33 | 192.168.1.62 |
| 192.168.1.64 | /26 | 192.168.1.127 | 192.168.1.65 | 192.168.1.69 | 192.168.1.70 | 192.168.1.126 |
| 192.168.1.128 | /26 | 192.168.1.191 | 192.168.1.129 | 192.168.1.143 | 192.168.1.144 | 192.168.1.190 |
## 🧩 Contributing
We welcome contributing. See CONTRIBUTING.md file for details
## ⚖️ License
This project is licensed under the GPL-3.0 License. See the LICENSE file for details.
## ⚔️ Contact
- For any inquiries or support, please contact iannacconegiovanni444@gmail.com .
- Visit my site for more informations about me and my work https://giovanni-iannaccone.github.io