kvm-qcow-shrink

kvm-qcow-shrink is a command-line tool written in Go that compresses QCOW2 image files used by KVM virtual machines. It automatically identifies QCOW2 images associated with a specified VM and efficiently compresses them.

Features

• Automatically identifies QCOW2 images for a specified KVM virtual machine
• Verifies that the VM is stopped before proceeding
• Uses an efficient single-step compression process
• Compresses QCOW2 images in place to optimize disk space
• Uses sudo to execute commands with necessary permissions

Notes

• This tool requires sudo privileges to run. Make sure you have the necessary permissions.
• Ensure the VM is stopped before running this tool. The tool will check this and exit if the VM is running.
• Always ensure you have a backup of your VM and its disk images before using this tool.
• The compression process may take some time depending on the size of your QCOW2 images.
• This tool modifies the original image files in place. Make sure you have enough free space on your disk to accommodate temporary files during the compression process.

Prerequisites

Before using kvm-qcow-shrink, ensure you have the following installed on your system:

• virsh command-line tool
• qemu-img command-line tool
• sudo access

Installation

Build the tool:

$ go build -o kvm-qcow-shrink

Usage

To use kvm-qcow-shrink, run the following command with sudo:

$ kvm-qcow-shrink <VM_NAME>

Replace <VM_NAME> with the name of the KVM virtual machine whose images you want to compress.

Example:

$ kvm-qcow-shrink ubuntu-server

The tool will then:

1. Check if the specified VM is stopped
2. Retrieve the VM's XML configuration
3. Identify all QCOW2 image files associated with the VM
4. Compress each QCOW2 image in place

License

This project is licensed under the MIT License - see the LICENSE for details.