---
title: "Guilherme Ferreira (@gferreir) | Hashnode"
description: "A tech guy doing tech things. Read the latest articles by Guilherme Ferreira on Hashnode."
url: "https://hashnode.com/@gferreir"
---

@gferreir

# Guilherme Ferreira

@gferreir · São Paulo, Brazil · Joined August 2026

A tech guy doing tech things

### [OpenShift application Day-2: 7 guardrails that refuse the bad state in Git](https://gferreir.hashnode.dev/openshift-day2-guardrails-automations?utm_source=hashnode&utm_medium=feed)

Seven controls in the application repository — cert-manager, digest, LimitRange, restricted-v2, PDB, ExternalSecret, and runbook\_url

12 min read · [gferreir.hashnode.dev](https://gferreir.hashnode.dev/openshift-day2-guardrails-automations?utm_source=hashnode&utm_medium=feed)

[Aug 28](https://hashnode.com/posts/openshift-day2-guardrails-automations/6a91dceb048f0eed9869786c)

### [Application troubleshooting on OpenShift: 10 commands before blaming the cluster](https://gferreir.hashnode.dev/openshift-troubleshooting-10-commands?utm_source=hashnode&utm_medium=feed)

A namespace-first runbook that separates application incidents from platform outages

12 min read · [gferreir.hashnode.dev](https://gferreir.hashnode.dev/openshift-troubleshooting-10-commands?utm_source=hashnode&utm_medium=feed)

[Aug 27](https://hashnode.com/posts/openshift-troubleshooting-10-commands/6a9087d430fa581fa9aefed3)

### [OpenShift Application Day-2: 7 Mistakes That Take Down the Service, Not the Cluster](https://gferreir.hashnode.dev/openshift-day2-mistakes-that-take-down-clusters?utm_source=hashnode&utm_medium=feed)

Route TLS, image digests, resources, SCCs, PDB, Secrets, and runbooks — what breaks in the namespace after the first deploy

13 min read · [gferreir.hashnode.dev](https://gferreir.hashnode.dev/openshift-day2-mistakes-that-take-down-clusters?utm_source=hashnode&utm_medium=feed)

[Aug 26](https://hashnode.com/posts/openshift-day2-mistakes-that-take-down-clusters/6a8f4eea39223af093083aca)

### [Kafka on OpenShift in 15 Minutes: From Zero to Cluster with Red Hat Streams for Apache Kafka](https://gferreir.hashnode.dev/kafka-on-openshift-in-15-minutes-from-zero-to-cluster-with-red-hat-streams-for-apache-kafka?utm_source=hashnode&utm_medium=feed)

A hands-on guide to deploying a production-ready Kafka cluster on OpenShift using the Strimzi operator

8 min read · [gferreir.hashnode.dev](https://gferreir.hashnode.dev/kafka-on-openshift-in-15-minutes-from-zero-to-cluster-with-red-hat-streams-for-apache-kafka?utm_source=hashnode&utm_medium=feed)

[Aug 21](https://hashnode.com/posts/kafka-on-openshift-in-15-minutes-from-zero-to-cluster-with-red-hat-streams-for-apache-kafka/6a8855107f217d597ea8118e)

### [Kafka for High Availability in Practice: Patterns with Red Hat Streams for Apache Kafka](https://gferreir.hashnode.dev/kafka-for-high-availability-in-practice-patterns-with-red-hat-streams-for-apache-kafka?utm_source=hashnode&utm_medium=feed)

5 HA patterns every Kafka deployment needs — from replication to cross-region disaster recovery

11 min read · [gferreir.hashnode.dev](https://gferreir.hashnode.dev/kafka-for-high-availability-in-practice-patterns-with-red-hat-streams-for-apache-kafka?utm_source=hashnode&utm_medium=feed)

[Aug 21](https://hashnode.com/posts/kafka-for-high-availability-in-practice-patterns-with-red-hat-streams-for-apache-kafka/6a8853e3e307eba2cdbdf588)