VLab

Is a personal experiment I created to learn more about virtualisation on masOS ARM64.

The vlab cli tool provides a utility that enables the serial start up and shutowm of VMs managed by Lima.

What Problem Is Being Solved

The core problem being solved is the ability to spin up and tear down a collection of VMs that are managed by Lima. I created this tool as a light-weight convenience utility that allows me to bring up and down multiple VMs managed by Lima.

Installer

/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/jcnnll/vlab/refs/heads/main/install.sh)"

Note: This script is used to install the dependencies as well as VLab to the machine. It will only run on macOS ARM64.

1. Environment Validation

Restricts the installation to macOS on ARM64 architecture.

2. Dependency Provisioning

The following dependencies are installed if missing:

• Xcode Command Line Tools
• Rosetta 2
• Lima
• socket_vmnet

3. System-Level Configuration

• Move socket_vmnet to a root protected path (/opt/socket_vmnet/)
• Enforce root:wheel ownership of socket_vmnet to satisfy Lima security requirements for privileged networking.
• Lima Rootless Execution (Sudoers)
  • Generate a dedicated sudoers config using limactl sudoers
  • Deploys to /etc/sudoers.d/lima with *440 permissions, allowing the VM network bridge to start without interactive password prompts.

4. VLab CLI Install

• Dynamically fetch the latest version of vlab package and checksums.
• Execute a shasum -a 256 check against the downloaded package before extraction to ensure file integrity.
• Extract and deploys the binary to /usr/local/bin
• Set executable permissions.

Usage

VLab acts as a sequential orchestrator to manage the lifecycle of your virtual infrastructure.

To avoid resource exhaustion on the host, vlab up and vlab down processes nodes in a blocking loop based on a simple manifest.

Lab Configuration (vlab.yaml)

Define your provisioning order in a flat list:

nodes:
  - dns
  - node-01
  - node-02

Note: the same naming convention used by Lima is applied to the vlab.yaml file. Only the file name is used to reference a VM instance.

CLI Commands

vlab up processes the vlab.yaml sequence and executes limactl start for each node. vlab down reverses the sequence to stop all nodes via limactl stop. vlab status provides a unified view of the environment state via limactl list.

Example Usage

As an example I created a single VM that is configured to run the DNS - this is an example of an experiment I ran to learn about DNS.