Kubernetes Service Mesh (Istio)

Traffic management, security, and observability using kubectl-mcp-server's Istio/Kiali tools.

Requires the cilium, istio toolsets: start kubectl-mcp-server with --toolsets default,cilium,istio (or MCP_TOOLSETS=default,cilium,istio).

When to Apply

Use this skill when:

• User mentions: "Istio", "service mesh", "mTLS", "VirtualService", "traffic shifting"
• Operations: traffic management, canary deployments, security policies
• Keywords: "sidecar", "proxy", "traffic split", "mutual TLS"

Priority Rules

Priority	Rule	Impact	Tools
1	Detect Istio installation first	CRITICAL	detect_ecosystem
2	Run analyze before changes	HIGH	istio_analyze
3	Check proxy status for sync	HIGH	istio_proxy_status
4	Verify sidecar injection	MEDIUM	istio_sidecar_status

Quick Reference

Task	Tool	Example
Detect Istio	detect_ecosystem	detect_ecosystem()
Analyze config	istio_analyze	istio_analyze(namespace)
Proxy status	istio_proxy_status	istio_proxy_status()
List VirtualServices	istio_virtualservices_list	istio_virtualservices_list(namespace)

Quick Status Check

Detect Istio Installation

detect_ecosystem()

Check Proxy Status

istio_proxy_status()
istio_sidecar_status(namespace)

Analyze Configuration

istio_analyze(namespace)

Traffic Management

VirtualServices

List and inspect:

istio_virtualservices_list(namespace)
istio_virtualservice_get(name, namespace)

See TRAFFIC-SHIFTING.md for canary and blue-green patterns.

DestinationRules

istio_destinationrules_list(namespace)

Gateways

istio_gateways_list(namespace)

Traffic Shifting Patterns

Canary Release (Weight-Based)

VirtualService for 90/10 split:

apiVersion: networking.istio.io/v1beta1
kind: VirtualService
metadata:
  name: my-service
spec:
  hosts:
  - my-service
  http:
  - route:
    - destination:
        host: my-service
        subset: stable
      weight: 90
    - destination:
        host: my-service
        subset: canary
      weight: 10

Apply and verify:

kubectl_apply(vs_yaml, namespace)
istio_virtualservice_get("my-service", namespace)

Header-Based Routing

Route beta users:

http:
- match:
  - headers:
      x-user-type:
        exact: beta
  route:
  - destination:
      host: my-service
      subset: canary
- route:
  - destination:
      host: my-service
      subset: stable

Security (mTLS)

See MTLS.md for detailed mTLS configuration.

PeerAuthentication (mTLS Mode)

istio_peerauthentications_list(namespace)

AuthorizationPolicy

istio_authorizationpolicies_list(namespace)

Observability

Proxy Metrics

istio_proxy_status()

Hubble (Cilium Integration)

If using Cilium with Istio:

get_hubble_flows(namespace)
cilium_list_endpoints(namespace)

Troubleshooting

Sidecar Not Injected

istio_sidecar_status(namespace)

Traffic Not Routing

istio_analyze(namespace)
istio_virtualservice_get(name, namespace)
istio_destinationrules_list(namespace)
istio_proxy_status()

mTLS Failures

istio_peerauthentications_list(namespace)

Common Issues

Symptom	Check	Resolution
503 errors	istio_analyze()	Fix VirtualService/DestinationRule
No sidecar	istio_sidecar_status()	Label namespace
Config not applied	istio_proxy_status()	Wait for sync or restart pod

Multi-Cluster Service Mesh

Istio multi-cluster setup:

istio_proxy_status(context="primary")
istio_virtualservices_list(namespace, context="primary")

istio_proxy_status(context="remote")

Prerequisites

• Istio: Required for all Istio tools

  istioctl install --set profile=demo
  

Related Skills

• k8s-deploy - Deployment with traffic shifting
• k8s-security - Authorization policies