microsrv Overview

What is microsrv?

microsrv is a modern developer cloud featuring scale-from-zero for both virtual machines (KVM) and isolated containers. Instances automatically sleep during idle periods and wake up in seconds on the first incoming TCP packet. You are billed only for active compute time (per-second vCPU and RAM accounting), while disks, IP addresses, and runtime configurations remain intact. An SSH gateway, HTTPS with automatic TLS, private VPCs, and WireGuard tunnels are included out of the box.

Under the hood, workloads run on high-performance bare metal host hypervisors. microsrv supports live migration across interruptible hosts to guarantee continuous uptime:

• Proactively tracks provider maintenance events and host reclamation signals.
• Performs seamless live migration of system memory (RAM) and active execution state of VMs and containers to standby nodes (< 50 ms pause).
• Preserves in-memory state, persistent disks (Stateful OverlayFS for containers), internal IP addresses, and active TCP connections.

[!NOTE] Applications running on your VMs and containers continue operating smoothly without restarting, dropping memory caches, or losing network sessions during host transfers.

Key Architectural Highlights

1. Serverless & Automatic Scale-from-Zero

Virtual machine and container instances stop when traffic ceases. Upon receiving an incoming packet, the instance resumes within seconds without redeployment, ensuring you only pay for active processing.

2. Seamless Live Migration Across Bare Metal Hosts

When an eviction warning or maintenance notice occurs, the orchestrator instantly selects a standby bare metal server and synchronizes memory state. Applications continue executing instructions without disruption.

3. Zero Public IP Security

In microsrv, guest VMs do not require public IP addresses.

• Terminal access goes through the SSH gateway:

  ssh my-vm@msrv.space

• Web applications and APIs are published through the HTTPS gateway with <vm>.msrv.space hostnames and TLS certificates.

4. High-Performance eBPF NAT

Every VM resides in an isolated Virtual Private Cloud (VPC) and retains outbound internet access for package updates, Git operations, and external API requests via kernel-level eBPF Outbound NAT.

[!TIP] eBPF routes and filters traffic directly inside the Linux kernel, ensuring near-bare-metal network performance and protection against IP/MAC spoofing.

Network Architecture & Traffic Topology

Next Steps

• Quickstart: Launch Your First VM
• Infrastructure as Code with OpenTofu
• Containers Overview
• Network Architecture & eBPF Isolation