Introduction

Linkerd viz dashboard shows no data when metrics API is not accessible. This guide provides step-by-step diagnosis and resolution with specific commands and configuration examples.

Symptoms

Typical symptoms and error messages when this issue occurs:

bash
Service mesh error: operation failed
Check proxy and control plane logs
kubectl logs -n istio-system deployment/istiod

Observable indicators: - Service mesh proxy logs show configuration errors - Control plane reports validation failures - Traffic routing does not match expected behavior

Common Causes

  1. 1.Linkerd issues are typically caused by:
  2. 2.Missing or incorrect annotations
  3. 3.Certificate issuer problems
  4. 4.CNI plugin misconfiguration
  5. 5.Control plane component failures

Step-by-Step Fix

Step 1: Check Current State

bash
linkerd check

Step 2: Identify Root Cause

bash
linkerd viz stat deploy -n <namespace>

Step 3: Apply Primary Fix

yaml
# Primary configuration fix
apiVersion: networking.istio.io/v1beta1
kind: VirtualService
metadata:
  name: my-service
spec:
  hosts:
  - "my-service"
  http:
  - route:
    - destination:
        host: my-service
        subset: v1

Apply this configuration:

bash
kubectl apply -f virtualservice.yaml

Step 4: Apply Alternative Fix (If Needed)

```bash # Verify configuration istioctl analyze

# Check proxy status istioctl proxy-status

# View effective configuration istioctl proxy-config all <pod-name> ```

Step 5: Verify the Fix

After applying the fix, verify with:

bash
linkerd check && linkerd viz stat deploy -n <namespace>

Expected output should show healthy proxies and correct routing.

Common Pitfalls

  • Missing namespace annotation
  • Identity issuer certificate expired
  • CNI plugin not installed correctly
  • Proxy resource limits too low

Best Practices

  • Use linkerd check for health verification
  • Configure proxy resources appropriately
  • Enable mTLS for all services
  • Use service profiles for routing
  • Linkerd Proxy Injection Label Missing
  • Linkerd Identity Issuer Error
  • Linkerd Service Profile Not Working
  • Linkerd TLS Not Enabled