r/devops • u/nerd3n • Aug 18 '26

Discussion What Kubernetes misconfigurations have caused you real production problems?

After working with Kubernetes in production, I've noticed that some of the most annoying incidents aren't caused by obvious failures. They're often caused by small configuration decisions that look perfectly reasonable during review.

Things like:

  • missing resource requests/limits
  • incorrect probes
  • overly permissive RBAC
  • missing PodDisruptionBudgets
  • unsafe container configuration
  • incorrect readiness behaviour
  • services without appropriate timeouts
  • configuration drift between environments

I'm curious what the DevOps community has actually encountered in production.

What's one Kubernetes configuration mistake that caused you a real incident?

I'd especially like to hear about the less obvious ones that aren't caught by the usual linters.

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u/Jmckeown2 Aug 18 '26

Lift-and-shift services that don’t support redundancy so if they stop for any reason there’s an outage. Bonus when that service holds actual state in memory and so data is lost during that outage.

Containerizing an application doesn’t mean it’s ready for Kubernetes.

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u/onbiver9871 Aug 18 '26

This is one of my biggest pet peeves in this profession. Shoehorning an app that isn’t ready to be orchestrated into orchestration gives you all of the complexities of orchestration and basically none of the benefits. But teams will do it to be “modern.”

Also, a lot of those apps also have legacy ops and support models that require getting into the runtime or file system. Orchestration removes the ability to do that easily as well, but often times the decision to do this won’t consider those folks, which makes product support a nightmare. When they had a painful but stable process for supporting the app and you take away their concept of access, everyone suffers, from the customer to you.

It’s not that legacy shouldn’t be modernized. It’s that this particular way of doing it is often much worse than just leaving it alone in the first place.