Observability with service mesh in Kubernetes - Step-by-Step Execution

Process Flow - Observability with service mesh

Service Mesh Installed

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Sidecar Proxy Injected

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Traffic Routed Through Proxy

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Telemetry Data Collected

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Data Sent to Observability Tools

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Metrics, Logs, Traces Visualized

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Issues Detected and Debugged

This flow shows how a service mesh adds proxies to services, collects telemetry data, and sends it to tools for monitoring and debugging.

Execution Sample

Kubernetes

kubectl apply -f istio.yaml
kubectl get pods --namespace istio-system
kubectl label namespace default istio-injection=enabled
kubectl apply -f sample-app.yaml
kubectl get svc
kubectl logs -l app=sample-app -c istio-proxy

These commands install a service mesh, enable sidecar injection, deploy an app, and show proxy logs for observability.

Process Table

Step	Command	Action	Result/Output
1	kubectl apply -f istio.yaml	Install Istio service mesh components	istio-system namespace created, pods starting
2	kubectl get pods --namespace istio-system	Check Istio pods status	Pods: istiod, ingressgateway running
3	kubectl label namespace default istio-injection=enabled	Enable automatic sidecar injection	Namespace 'default' labeled
4	kubectl apply -f sample-app.yaml	Deploy sample app with sidecar proxies	Pods created with istio-proxy containers
5	kubectl get svc	List services including mesh-enabled ones	Services: sample-app listed
6	kubectl logs -l app=sample-app -c istio-proxy	View proxy logs for telemetry data	Logs show traffic routing and telemetry events
7	Exit	All components running and telemetry collected	Observability data ready for analysis

💡 All pods are running with sidecar proxies; telemetry data is collected and visible in logs.

Status Tracker

Variable	Start	After Step 1	After Step 3	After Step 4	Final
istio-system pods	0	Starting	Running	Running	Running
default namespace label	none	none	istio-injection=enabled	istio-injection=enabled	istio-injection=enabled
sample-app pods	0	0	0	Created with sidecar	Running with sidecar
telemetry logs	empty	empty	empty	populated	populated

Key Moments - 3 Insights

Why do we label the namespace with 'istio-injection=enabled'?

Labeling the namespace triggers automatic injection of sidecar proxies into pods created in that namespace, as shown in execution_table step 3 and 4.

What is the role of the 'istio-proxy' container in the sample app pods?

The 'istio-proxy' container acts as a sidecar proxy that intercepts traffic and collects telemetry data, visible in logs at step 6.

How do we know telemetry data is being collected?

Telemetry data appears in the logs of the istio-proxy container, as shown in execution_table step 6.

Visual Quiz - 3 Questions

Look at the execution table, at which step is the sidecar proxy injected into the sample app pods?

A Step 2

B Step 3

C Step 4

D Step 1

💡 Hint

Check the action and result columns for pod creation with sidecar proxies in step 4.

According to the variable tracker, what is the state of telemetry logs after step 4?

A populated

B empty

C starting

D unknown

💡 Hint

Look at the 'telemetry logs' row under 'After Step 4' column.

If the namespace label 'istio-injection=enabled' was missing, what would change in the execution table?

A Istio pods would not start in step 1

B Sidecar proxies would not be injected in step 4

C Sample app pods would fail to create in step 4

D Telemetry logs would be populated earlier

💡 Hint

Refer to step 3 and 4 where labeling triggers sidecar injection.

Concept Snapshot

Observability with Service Mesh:
- Install service mesh (e.g., Istio) in cluster
- Label namespaces to enable sidecar proxy injection
- Deploy apps; proxies collect telemetry
- Use logs, metrics, traces for monitoring
- Helps detect and debug service issues easily

Full Transcript

Observability with a service mesh means adding a layer that automatically inserts small proxy containers next to your app containers. These proxies watch all the network traffic going in and out. First, you install the service mesh components in your Kubernetes cluster. Then, you label the namespace where your apps run to enable automatic sidecar proxy injection. When you deploy your app, each pod gets a proxy container. This proxy collects telemetry data like logs, metrics, and traces. You can view this data by checking the proxy logs or using observability tools. This setup helps you see how your services communicate and quickly find problems.