Overview#

GritivaCore VNet is an overlay network that connects a set of scopes across one or many virtual machines (VMs) into a single private network. It utilizes WireGuard (gmesh) and Linux network namespaces to create a secure and efficient networking solution. This document outlines the key features, use cases, and technical specifications of VNets within the GritivaCore ecosystem.

What is VNet?#

A VNet (Virtual Network) in GritivaCore is a Wave A primitive that provides a private network with its own subnet, routing table, and DNS. It is defined by the following characteristics:

• A CIDR (IPv4 only currently)
• A list of attached scopes (membership)
• A per-scope IP allocation
• Optional egress NAT rules
• Per-edge firewall rules

ASCII Diagram#

VM1: Scope1  ----|
                |-- VNet (10.x.x.x)
VM1: Scope2  ----|

VM2: Scope1  ----|
                |-- VNet (10.x.x.x)
VM2: Scope2  ----|

Key Features#

• Wave A vs Wave B: Wave A is overlay only (gmesh-based). Wave B adds vRouter/vSwitch/vLB primitives.
• Lifecycle Commands:
  • gritivactl vnet create my-net --cidr 10.42.0.0/16
  • gritivactl vnet attach my-net --scope my-app
  • gritivactl vnet detach my-net --scope my-app
  • gritivactl vnet list
• IP Allocation: The first attached scope gets .0.10, the next .0.11, etc. Static reservations are possible.
• Cross-VM Behavior: Scopes on different VMs can reach each other through gmesh peers without a central router.
• Common Pitfalls:
  • MTU mismatch when nesting.
  • DNS not propagated to scope automatically (you bind /etc/resolv.conf yourself).

Use Cases#

VNets are ideal for scenarios where secure, private communication between multiple VMs is required, such as:

• Multi-tier applications where different components run on separate VMs.
• Development and testing environments that require isolation from production networks.
• Secure communication between microservices.

Comparison with Traditional Networks#

Unlike traditional networks that rely on physical infrastructure, VNets provide a flexible and scalable solution that can adapt to changing workloads and requirements. Key differences include:

• Scalability: VNets can easily scale by adding or removing VMs without reconfiguring physical hardware.
• Security: VNets offer enhanced security through isolation and encryption, reducing the attack surface.

Technical Specifications#

• Protocol: Built on WireGuard (gmesh).
• IP Addressing: Supports IPv4 CIDR notation.
• Performance: Optimized for low-latency communication between VMs.

Conclusion#

GritivaCore VNet provides a robust solution for creating secure, private networks across multiple VMs. Its overlay architecture and integration with WireGuard make it a powerful tool for modern cloud environments.