Introduction
Kubernetes works brilliantly in demos.
Clusters come up. Pods run. Services respond.
Everything looks healthy — until real traffic, real data, and real users arrive.
Most production issues blamed on Kubernetes are not Kubernetes problems at all.
They’re the result of default configurations that were never meant for production.
This post explains why Kubernetes defaults fail in real environments, the most common areas teams ignore, and how to think about Kubernetes configuration responsibly.
Defaults Are Designed for Convenience, Not Reality
Kubernetes defaults exist to:
- Lower the entry barrier
- Make experimentation easy
- Avoid opinionated assumptions
They are not optimized for:
- Cost efficiency
- Security hardening
- Performance predictability
- Multi-tenant workloads
- Long-running systems
Running production workloads on defaults is like deploying software with:
- Debug mode enabled
- No limits
- No alerting
- No failure planning
It works — until it matters.
1. Resource Requests and Limits Are Optional (That’s the Problem)
By default:
- Kubernetes does not enforce resource requests or limits
- Pods can consume whatever the node allows
Many teams:
- Skip requests/limits initially
- “Plan to add them later”
- Never actually do
What goes wrong
- Nodes get overcommitted
- Critical pods get evicted
- CPU throttling causes latency spikes
- Autoscalers behave unpredictably
Production lesson:
If resources are optional, instability is guaranteed.
2. Security Defaults Are Permissive by Design
Out of the box, Kubernetes allows:
- Containers running as root
- Broad network communication
- Minimal pod-level isolation
- Weak runtime restrictions
This isn’t negligence — it’s compatibility.
But in production:
- Attack surface matters
- Compliance matters
- Blast radius matters
What goes wrong
- Security issues are discovered post-deployment
- Fixes require disruptive changes
- Teams blame Kubernetes instead of configuration
Production lesson:
Security must be explicit — defaults won’t protect you.
3. Networking Defaults Don’t Scale With Complexity
Default Kubernetes networking assumes:
- Flat communication
- Minimal segmentation
- Trust between services
As systems grow:
- East-west traffic increases
- Debugging becomes harder
- One misbehaving service impacts many others
What goes wrong
- Noisy services overwhelm others
- Debugging network issues becomes guesswork
- Security teams demand late-stage controls
Production lesson:
Unrestricted networking is fine for demos — dangerous at scale.
4. Storage Defaults Hide Long-Term Cost and Risk
Most clusters:
- Use the default StorageClass
- Accept default volume sizes
- Ignore reclaim policies
This works — quietly.
What goes wrong
- Storage costs grow invisibly
- Orphaned volumes accumulate
- Backup and restore paths are unclear
By the time someone notices, cleanup is painful.
Production lesson:
Storage defaults optimize for speed, not sustainability.
5. Observability Defaults Create Noise, Not Insight
Kubernetes exposes:
- Massive metrics
- Verbose logs
- Event floods
Without intentional design:
- Everything gets collected
- Nothing gets prioritized
What goes wrong
- Monitoring systems become expensive
- Alerts lack context
- Teams ignore dashboards entirely
Production lesson:
More data does not mean better observability.
Why Defaults Survive in Production
Defaults persist because:
- “It’s working”
- No one owns configuration quality
- Early shortcuts become permanent
- Problems show up months later
By the time defaults cause visible issues, fixing them feels risky.
A Better Production Mindset for Kubernetes
Instead of asking:
“Does this work?”
Ask:
“Is this intentional?”
Practical principles:
- Explicitly define resources
- Harden security early
- Limit communication paths
- Design storage lifecycle
- Collect only meaningful signals
Defaults should be starting points, not destinations.
When Defaults Are Acceptable
Defaults are fine when:
- You’re learning Kubernetes
- You’re testing locally
- You’re running short-lived workloads
Defaults are dangerous when:
- Data matters
- Uptime matters
- Cost matters
- Security matters
That’s most production environments.
Final Thoughts
Kubernetes didn’t fail your production system.
Ambiguous configuration did.
Defaults exist to get you started — not to carry your system indefinitely.
Production stability comes from intentional decisions, not inherited assumptions.
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