A real-world guide for DevOps engineers who want zero-downtime upgrades and zero post-mortems The Story That Started This Guide The alert came in at 9:47 PM. “API server unreachable.” The on-call engineer opened his laptop to find that the cluster upgrade — which was “just a version bump from 1.27 to 1.28” — had gone completely sideways. The … Read more
Picture this: it’s a Tuesday afternoon. Your infra team is draining a node for routine maintenance. Looks straightforward. Then your monitoring goes red — every single replica of your payment service got evicted at the same time. Zero pods up. Full outage. Nobody planned for that. Nobody set any guardrails. And that’s exactly the problem … Read more
It’s 11 PM. Your deployment just went out. Slack is blowing up. You check the cluster and see it — that dreaded status: NAME READY STATUS RESTARTS AGEmy-app-7d9f8b 0/1 CrashLoopBackOff 8 12m Eight restarts. Climbing. And you have no idea why. If you’ve worked with Kubernetes for more than a week, you’ve seen this. CrashLoopBackOff … Read more
You ran kubectl apply, your terminal said “pod created,” but the app is still down. Sound familiar? I’ve been there. 2 AM. Production alert firing. Pod shows Running but requests are failing. No obvious errors. That’s when I realized — I didn’t actually understand the Pod lifecycle. I just knew enough to deploy things and pray. Once I … Read more