Redhat on Rafael Zago

OpenShift Service Mesh 3: multi-cluster with ACM and Kiali

Thu, 23 Jul 2026 00:00:00 -0300

Multi-cluster with a service mesh usually fails on the boring detail: meshID, clusterName, and network have to match everywhere. If one diverges, Kiali shows half a topology or inter-cluster traffic never finishes the handshake. Installing the control plane twice does not fix that.

In the post about OpenShift Service Mesh 3 I covered the move from Maistra to upstream Istio. This is the next step: two spokes in the same multi-primary mesh, with ACM on the hub.

OpenShift Service Mesh 3: what changes with Istio

Mon, 07 Jul 2025 00:00:00 -0300

Overview

OpenShift Service Mesh 3 (OSSM3) replaces Maistra with upstream Istio as the core of the solution. Maistra was a Red Hat-maintained custom fork of Istio; with OSSM3, the base is Istio straight from the community project — no custom patches, no rebase.

Concrete changes include: control plane upgrades can be in-place or revision-based (canary), Kiali must be installed separately via the Kiali Operator, and multi-cluster support uses the standard upstream Istio topologies.

Real-Time Linux: low latency with PREEMPT_RT

Fri, 20 Dec 2024 00:00:00 -0300

Introduction

Real-Time Linux (RTL) is a Linux kernel extension that turns the operating system into a real-time environment. On top of the usual Linux features, it can handle work that needs high predictability and low latency—industrial automation, medical devices, even entertainment systems.

At the end of 2024, the Linux kernel fully absorbed Real-Time Linux (RTL). That was a historic milestone. How did we get here?

The RTL journey

The idea of adding real-time capabilities to Linux goes back to the late 1990s, when the first patches aimed to improve performance and cut kernel latency. Those patches grew into more solid projects such as PREEMPT-RT.

Skupper workshop: Patient Portal on Kubernetes

Tue, 02 Jul 2024 00:00:00 -0300

Description

This workshop introduces Red Hat Service Interconnect, an application integration solution that lets different systems communicate efficiently and securely.

Solution architecture

Service topology

Workshop outline

Sign in to Red Hat Developer.
Create an OpenShift cluster.
Access the OpenShift cluster.
In the Red Hat OpenShift Sandbox project, open your project.
Create a virtual machine with OpenShift Virtualization.
Install packages on the virtual machine:
- podman
- kubernetes-client
- skupper
- oc
- wget
Deploy the database with Podman.
Deploy the application frontend and backend.
Configure Service Interconnect (Skupper) so the database running under Podman can talk to the app on OpenShift.
Access the application and confirm communication works.
Closing notes.

Links

Resource	Link
[1] Red Hat Developer	https://developers.redhat.com/
[2] OC	https://docs.openshift.com/container-platform/4.15/cli_reference/openshift_cli/getting-started-cli.html
[3] Skupper	https://skupper.io/

Prerequisites

A Red Hat Developer account
Basic Kubernetes knowledge
Basic Red Hat OpenShift knowledge
Basic Podman knowledge
Google Chrome preferred—it lets you paste commands into the VM console over browser VNC.

Step by step

Go to Red Hat Developer and sign in with your account.

Who am I? About Rafael Zago

Mon, 04 Dec 2023 00:00:00 -0300

Introduction

Qué pasa?

Hi. Don’t take me too seriously, okay? I built this space to share a bit of what I know—and about 90% of it came from the internet. So it was past time to give some of it back.

Today I’m a senior software automation engineer at Red Hat. Before that I bounced through a few companies, small and large, doing a bit of everything:

DevOps at heart, sysadmin by vocation.
Building learning methods and structuring training.
Years of application support across all sizes and complexity levels.
Instructor at Caelum/Alura.
Godfather to the coolest kid on the planet. No bias here…

Communities

I’m a DevOps person at heart and also part of the DevOpsDays SP organizing team.

CI/CD upstream vs downstream: when to use each

Fri, 02 Jun 2023 00:00:00 -0300

Integrating Skupper upstream and downstream

Integrating upstream and downstream projects is rarely simple. Here is a practical approach for Skupper on the upstream side and its commercial downstream line, using familiar tools for each side of the work.

Introduction

Skupper is an open-source project that provides a service network for Kubernetes. It is developed by Red Hat and released under the Apache 2.0 license. That is the upstream version—the one under active development.

Skupper: multicloud app network in a few commands

Sat, 01 Oct 2022 00:00:00 -0300

References and technologies used

Tools

A computer with minikube [2] installed;
A terminal to run the commands;
kubectl > 1.15 [6] or newer.

Solution overview

Skupper [1] lets you connect two or more cloud environments in a non-intrusive, secure way. Those environments can sit on different cloud providers—AWS, GCP, Azure, and others—or on native Kubernetes clusters.

Redhat on Rafael Zago

OpenShift Service Mesh 3: multi-cluster with ACM and Kiali

OpenShift Service Mesh 3: what changes with Istio

Overview

Real-Time Linux: low latency with PREEMPT_RT

Introduction

The RTL journey

Skupper workshop: Patient Portal on Kubernetes

Description

Solution architecture

Service topology

Workshop outline

Links

Prerequisites

Step by step

1. Sign in to Red Hat Developer

Who am I? About Rafael Zago

Introduction

Communities

CI/CD upstream vs downstream: when to use each

Integrating Skupper upstream and downstream

Introduction

Skupper: multicloud app network in a few commands

References and technologies used

Tools

Solution overview