Virtual Machine Architecture

Before reading this document, be sure to review Istio’s architecture and deployment models. This page builds on those documents to explain how Istio can be extended to support joining virtual machines into the mesh.

Istio’s virtual machine support allows connecting workloads outside of a Kubernetes cluster to the mesh. This enables legacy applications, or applications not suitable to run in a containerized environment, to get all the benefits that Istio provides to applications running inside Kubernetes.

For workloads running on Kubernetes, the Kubernetes platform itself provides various features like service discovery, DNS resolution, and health checks which are often missing in virtual machine environments. Istio enables these features for workloads running on virtual machines, and in addition allows these workloads to utilize Istio functionality such as mutual TLS (mTLS), rich telemetry, and advanced traffic management capabilities.

The following diagram shows the architecture of a mesh with virtual machines: