Istio

Sidecarless? Why not podless?

How Istio tests its networking proxy without Kubernetes, Docker, or root.

tl;dr: it just works

Like most other Kubernetes controllers in, Istio is written in Go and relies on the client-go library. While this provides an excellent low-level building block, usage in higher level code in Istio led to a variety of issues that led us to develop our own higher level, opinionated client for Istio. This post covers the issues we faced and how we incrementally solved them. Background knowledge At a high level, client-go provides a few layers for interactions with the API server:...

Which features I recommend using, or not using, in Istio

Exploring an extreme service mesh architecture to maximize extensibility.

The OSI model attempts to build a model for network communications, where increasingly high level layers are built upon lower layers. This is only slightly useful in practice, as the real world is not so simple. In service mesh, generally discussion is reduced to L4 and L7, or TCP and HTTP. This oversimplifies the problem, leading to some confusion. Thinking in terms of termination Simply saying "HTTP" is not really clear about what is going on....

When looking at service mesh (or even general networking) architectures, the basic idea is to send network traffic through some component, which handles various functionality. This could be authentication, authorization, encryption, observability, reliability, networking, etc. There are a few different classes of components that can do this, though: Different types of proxy deployments Native application enhancement. The application itself is compiled in with functionality. This could be something like gRPC (or, even more "meshy", gRPC with xDS), Finagle, Hystrix, etc....

The common messaging around Istio Ambient Mesh is that is a "node proxy." For example, from The New Stack ... architecture that moves the proxy functionality from the pod-level to the node-level. While this is technically accurate, it is misleading and really missing the point and benefits of Ambient. A brief history of service mesh architectures This skips quite a bit of information, but is close enough. One of the earlier service meshes on the market was Linkerd 1 - not to be confused with Linkerd 2, which most people just call "Linkerd" today....

How to achieve an architecture similar to "Waypoint Proxies" without ambient mesh, or even Istio.