GKE Observability

This reference covers monitoring, logging, and metrics configuration for GKE. The golden path enables comprehensive observability including control-plane metrics.

MCP Tools: get_cluster, list_k8s_events, get_k8s_logs, get_k8s_cluster_info, describe_k8s_resource. CLI-only: gcloud container clusters update --monitoring=..., gcloud logging read

Golden Path Observability Defaults

Setting	Golden Path Value	Notes
`loggingConfig` components	SYSTEM_COMPONENTS, WORKLOADS	Full workload logging
`monitoringConfig` components	SYSTEM_COMPONENTS, STORAGE, POD, DEPLOYMENT, STATEFULSET, DAEMONSET, HPA, JOBSET, CADVISOR, KUBELET, DCGM, APISERVER, SCHEDULER, CONTROLLER_MANAGER	Full suite including control-plane
`managedPrometheusConfig.enabled`	`true`	Google-managed Prometheus
`advancedDatapathObservabilityConfig.enableMetrics`	`true`	Dataplane V2 flow metrics
`loggingService`	`logging.googleapis.com/kubernetes`	Cloud Logging
`monitoringService`	`monitoring.googleapis.com/kubernetes`	Cloud Monitoring

Control-Plane Metrics (Golden Path Addition)

The golden path adds three control-plane monitoring components not present in default clusters:

Component	What It Monitors
`APISERVER`	API server request latency, error rates, admission
: : webhook performance :
`SCHEDULER`	Scheduling latency, pending pods, scheduling failures
`CONTROLLER_MANAGER`	Controller work queue depth, reconciliation latency

These are critical for diagnosing cluster-level issues (slow API responses, scheduling delays, stuck controllers).

Enabling Full Monitoring

bash

# Enable golden path monitoring suite
gcloud container clusters update <CLUSTER_NAME> --region <REGION> \
  --monitoring=SYSTEM,API_SERVER,SCHEDULER,CONTROLLER_MANAGER,STORAGE,POD,DEPLOYMENT,STATEFULSET,DAEMONSET,HPA,CADVISOR,KUBELET,DCGM \
  --quiet

# Enable Managed Prometheus
gcloud container clusters update <CLUSTER_NAME> --region <REGION> \
  --enable-managed-prometheus \
  --quiet

# Enable Dataplane V2 observability metrics
gcloud container clusters update <CLUSTER_NAME> --region <REGION> \
  --enable-dataplane-v2-flow-observability \
  --quiet

Managed Prometheus

Golden path enables Google Managed Prometheus for metrics collection and querying.

Querying metrics:

Use Cloud Monitoring Metrics Explorer in the console
Use PromQL via the Prometheus UI or API
Grafana dashboards via Managed Grafana

Key GKE metrics:

Metric	Source	Use
`container_cpu_usage_seconds_total`	cAdvisor	Pod CPU usage
`container_memory_working_set_bytes`	cAdvisor	Pod memory
: : : usage :
`kube_pod_status_phase`	kube-state-metrics	Pod lifecycle
`apiserver_request_duration_seconds`	API Server	Control plane
: : : latency :
`scheduler_scheduling_duration_seconds`	Scheduler	Scheduling
: : : performance :
`node_cpu_seconds_total`	Kubelet	Node CPU
`DCGM_FI_DEV_GPU_UTIL`	DCGM	GPU
: : : utilization :

Live Resource Usage (kubectl-only)

No MCP or gcloud equivalent exists for live resource usage. Use kubectl top:

bash

kubectl top pods --all-namespaces --sort-by=cpu
kubectl top nodes
kubectl top pods --containers -n <NAMESPACE>  # per-container breakdown

Cloud Logging (gcloud-only)

Querying cluster logs (no MCP equivalent — use gcloud logging read):

bash

# System component logs
gcloud logging read \
  'resource.type="k8s_cluster" AND resource.labels.cluster_name="<CLUSTER_NAME>"' \
  --project <PROJECT_ID> --limit 50 \
  --quiet

# Workload logs for a specific namespace
gcloud logging read \
  'resource.type="k8s_container" AND resource.labels.cluster_name="<CLUSTER_NAME>" AND resource.labels.namespace_name="<NAMESPACE>"' \
  --project <PROJECT_ID> --limit 50 \
  --quiet

# Audit logs (who did what)
gcloud logging read \
  'resource.type="k8s_cluster" AND logName:"cloudaudit.googleapis.com"' \
  --project <PROJECT_ID> --limit 50 \
  --quiet

Diagnostic Settings

For security monitoring and troubleshooting, enable control-plane audit logs:

bash

# View current logging config
gcloud container clusters describe <CLUSTER_NAME> --region <REGION> \
  --format="yaml(loggingConfig)" \
  --quiet

Alerting

Set up alerts for critical conditions:

Condition	Metric	Threshold
High API server latency	`apiserver_request_duration_seconds`	P99 > 5s
Pod crash loops	`kube_pod_container_status_restarts_total`	> 5 in 10min
Node not ready	`kube_node_status_condition`	condition=Ready, status!=True
High GPU utilization	`DCGM_FI_DEV_GPU_UTIL`	> 95% sustained
PVC near capacity	`kubelet_volume_stats_used_bytes / capacity`	> 85%
Scheduling failures	`scheduler_schedule_attempts_total{result="error"}`	> 0

Proposing Dashboards & Alerts (Production Rules)

When designing or proposing alerting and dashboard strategies for GKE:

Always explicitly name Google Cloud Monitoring as the platform to implement these alerts and dashboards.
Always include API server latency (via apiserver_request_duration_seconds metric) on the dashboard as a critical indicator of control plane health, alongside node CPU/Memory and pod crash loops.

Cost Considerations

Monitoring and logging have associated costs:

Cloud Logging: Charged per GiB ingested beyond free tier (50 GiB/project/month)
Cloud Monitoring: Free for GKE system metrics; custom metrics charged per time series
Managed Prometheus: Charged per samples ingested

To reduce costs in non-production:

bash

# Reduce to system-only monitoring
gcloud container clusters update <CLUSTER_NAME> --region <REGION> \
  --monitoring=SYSTEM \
  --quiet

Distributed Tracing & Continuous Profiling (Recommended)

Not golden path defaults — recommended for production microservice architectures and performance-sensitive workloads.

Cloud Trace: Add OpenTelemetry SDK to your app with the opentelemetry-operations-go (or equivalent) exporter. Traces appear in Cloud Trace console. Identifies cross-service latency bottlenecks.
Cloud Profiler: Add the Cloud Profiler agent to your app. Profiles CPU and memory usage in production with low overhead. Identifies hotspots and compares across versions.

LQL Query Examples

Common Logging Query Language patterns for GKE troubleshooting:

text

# Error logs for a specific container
resource.type="k8s_container" AND resource.labels.container_name="my-app" AND severity>=ERROR

# OOMKilled events
resource.type="k8s_event" AND jsonPayload.reason="OOMKilling"

# Pod scheduling failures
resource.type="k8s_event" AND jsonPayload.reason="FailedScheduling"

# Audit logs (who did what)
resource.type="k8s_cluster" AND logName:"cloudaudit.googleapis.com"