Kubernetes networking diagnosis training for application and platform engineers

Private, instructor-led training for engineers who expose Kubernetes applications and need to identify where a failed request stops along an existing traffic path.

Working manifests do not establish working connections. DNS answers, endpoint membership, readiness, proxies, and policy provide different evidence, and a timeout alone does not identify the failing layer.

LearnKube traces a representative request through the platform. Engineers compare observations at successive boundaries, make a targeted correction, and verify the original application behavior.

Discuss your team's training

Hands-on learning and the skills engineers take back to work.

Preview: course-wide figures are not yet available.

  • Hands-on learning
    60%
    Of instruction time spent on labs and challenges.
  • Troubleshooting confidence
    86%
    Of respondents report greater confidence diagnosing Kubernetes problems.
  • Relevant to your work
    92%
    Of respondents say the course addressed their engineering responsibilities.
  • Skills put into practice
    95%
    Of respondents applied their new skills at work within 90 days.

Trace the request before changing the network

  • Explain the traffic path through discovery, endpoint selection, and proxy behavior, so engineers can predict which component handles each stage.
  • Diagnose a failed connection using DNS results, endpoint state, policy evidence, and request observations, so the team can distinguish possible causes.
  • Validate a correction from the original client's position, so a successful backend probe is not mistaken for end-to-end recovery.
  • Make diagnosis repeatable through a path diagram and ordered observations, so another engineer can investigate without guessing which component to restart.

Name resolution is not proof of reachability

The team already creates Services and ingress resources, but their existence does not establish a complete request path. Service diagnosis separates name resolution, ports, selectors, and backend responses. EndpointSlice conditions describe additional readiness and termination state. Engineers need to compare these observations with the client path before attributing failure to the ingress controller or network.

I want the engineer to say which boundary a successful probe actually tested. A response from a Pod address does not prove that DNS, Service selection, and the external ingress path work for the original client.

— Daniele Polencic, LearnKube founder and Kubernetes instructor

Production questionMechanism to understandPractice
Does the name resolve?DNS scope and recordsCompare client lookup results
Are backends eligible?Selectors and endpoint conditionsInspect selected replicas
Where does traffic stop?Proxies, ports, and policyTrace successive request boundaries
Is the original path restored?End-to-end application behaviorRepeat the client request

Case Study: Bloomberg

Bloomberg's on-prem Kubernetes questions included Envoy ingress, authentication and authorization, network policies, and service meshes. LearnKube delivered private Kubernetes training for the team.

Asked what she liked most about the course, Grace identified the practical work:

The labs

— Grace, Software Engineer at Bloomberg.

A proposed four-day workshop on request-path investigation

We use one application path throughout the course. Familiar setup is shortened so each module can add evidence about how requests reach, or fail to reach, that application.

Day 1

Explain probes, labels, ports, and rollout behavior. Compare a healthy process with an endpoint that is eligible to receive the intended traffic.

Hands-on exercises

  • Find a Service selector or port mismatch using workload evidence.
  • Observe how a release changes the eligible backends.

Day 2

Connect Helm or Kustomize output to Services, endpoint controllers, and node networking components. Identify whether live configuration matches the intended route.

Hands-on exercises

  • Compare rendered network resources with the objects and endpoints in use.
  • Trace an endpoint change after a workload replacement.

Day 3

Follow the request through internal discovery and the selected external routing implementation. Distinguish native networking from any mesh or authentication layer in the path.

Hands-on exercises

  • Investigate the same symptom from client, proxy, and backend positions.
  • Identify a policy or authentication decision without disabling unrelated controls.

Day 4

Examine resource pressure, persistent connections, credentials, and autoscaling effects on the path. Define the observations required to validate a change and make the investigation repeatable.

Hands-on exercises

  • Repeat a corrected request path under a bounded workload change.
  • Produce a path-specific diagnostic record another engineer can follow.

Your ingress, network integrations, and diagnostic questions can shape the agenda. Get in touch to tailor the workshop to your team's work.

Ask what a successful probe leaves untested

When an engineer concludes that the network works after reaching a Pod directly, the instructor can return to the original client path. The comparison exposes the unchecked DNS, Service, proxy, or policy boundary.

Bring the request paths your team supports

Tell us which network components your team operates, where it loses confidence during diagnosis, and which traffic paths it owns. We will recommend investigations and a suitable starting depth.

Discuss your team's training