Learn DevOps, Kubernetes & AWS — Simplified
Practical tutorials, deep dives, and battle-tested guides for engineers who build and ship in the cloud.
By KP | TZoneLabs | DevOps & Cloud Engineering During a traffic spike, every app server started throwing the same generic message: ETIMEDOUT. Nothing named the database. Nothing named the connection pool. So for the first hour, we debugged the network, the load balancer, and the application code, in that order, before anyone checked how … Read more
By KP | TZoneLabs | DevOps & Cloud Engineering Every rolling deploy for two months sent a burst of 502 errors to a small percentage of users, for about 30 seconds each time. Support tickets blamed “the app being slow sometimes.” The actual cause: our readiness probe was checking a port the container wasn’t listening … Read more
By KP | TZoneLabs | DevOps & Cloud Engineering For three weeks, our staging database password was sitting in plain text in every CI job log a specific pipeline produced. Anyone with read access to the project, which included a few external contractors, could open a job log and copy it out. Nobody stole it, … Read more
By KP | TZoneLabs | DevOps & Cloud Engineering The default .gitlab-ci.yml most teams start with runs npm ci or pip install in every single job, on every single commit. A pipeline with a build, test, and lint job doing the same install three times isn’t three times safer. It’s three times slower for no … Read more
By KP | TZoneLabs | DevOps & Cloud Engineering For nine days, our cluster added and removed the same three worker nodes every six minutes. Every dashboard we watched stayed green the whole time. Pods were running, nodes were Ready, CPU never crossed 60%. Nobody noticed until the AWS bill landed about 40% higher than … Read more
By KP | TZoneLabs | DevOps & Cloud Engineering An AccessDenied error from AWS tells you almost nothing. It names the action and sometimes the resource, but never which of the five places a permission could be blocked actually blocked it. We used to open the IAM console and read policies line by line, sometimes … Read more
By KP | TZoneLabs | DevOps & Cloud Engineering At 3 AM, our ingress started rejecting every HTTPS request with a certificate error. Every health check we had was green. Every pod was Running. The cluster looked perfectly healthy because none of our monitoring ever asked the one question that mattered: how many days is … Read more
By KP | TZoneLabs | DevOps & Cloud Engineering The fastest way to grant a pod too much power in Kubernetes is kubectl create clusterrolebinding temp –clusterrole=cluster-admin –serviceaccount=default:default. It works immediately, which is exactly the problem. Nobody circles back to fix it, and six months later a compromised pod can read every secret in the … Read more
By KP | TZoneLabs | DevOps & Cloud Engineering A PodDisruptionBudget doesn’t protect your application — it protects a number. That’s why a routine EKS managed node group upgrade recently stalled on us for 40 minutes and paged on-call at 2am, even though our minAvailable: 2 config was textbook. The PDB was doing exactly what … Read more
By KP | TZoneLabs | DevOps & Cloud Engineering Most engineers size EKS nodes by CPU and memory. We did too — until one day a pod sat in Pending, the node had plenty of compute free, and the events said something about failing to assign an IP. That was our introduction to the quietest … Read more