Runbook 03 — Kubernetes Architecture Review

Runbook Information

Item	Details
Runbook ID	K8S-RB-03
Category	Architecture Review
Difficulty	Advanced
Estimated Time	2–4 Hours
Environment	Amazon EKS / Azure AKS / Google GKE / On-Prem Kubernetes
Platform	Enterprise Kubernetes
Primary Role	Kubernetes Security Engineer
Team	Cloud Security Architecture
Escalation	Cloud Platform Architect

Scenario

CloudNova Technologies has completed the implementation of a new Kubernetes platform that will host multiple enterprise applications.

Before onboarding production workloads, the Cloud Architecture Review Board (ARB) requires an independent technical review of the platform architecture.

As a Kubernetes Security Engineer, you have been asked to validate that the platform architecture follows enterprise design principles for:

High Availability
Security
Scalability
Operational Excellence
Reliability
Cost Optimisation
Governance

The findings from this review will determine whether the platform can be approved for production.

Objectives

Review the Kubernetes platform architecture across the following domains:

Platform Design
Control Plane
Worker Nodes
Networking
Storage
Identity
Security Architecture
Monitoring
Disaster Recovery
Scalability
Operational Readiness

Architecture Review Workflow

Platform Overview
        │
        ▼
Architecture Review
        │
        ▼
Security Review
        │
        ▼
Scalability Review
        │
        ▼
Resilience Review
        │
        ▼
Operational Review
        │
        ▼
Architecture Assessment Report

Success Criteria

The platform architecture should demonstrate:

High Availability
Fault Tolerance
Defence in Depth
Least Privilege
Secure Networking
Secure Storage
Production Monitoring
Disaster Recovery
Operational Governance

Review Phase 1 — Platform Overview

Collect baseline platform information.

kubectl cluster-info

kubectl version

kubectl get nodes -o wide

Document:

Cluster Name
Kubernetes Version
Cloud Provider
Number of Worker Nodes
Number of Availability Zones
Container Runtime

Review Phase 2 — Control Plane Architecture

Review the Control Plane.

kubectl get pods -n kube-system

Confirm:

kube-apiserver
etcd
kube-controller-manager
kube-scheduler

Review architecture.

Users

↓

API Server

↓

Authentication

↓

Authorization

↓

Admission Controllers

↓

etcd

Architecture Questions

Is the Control Plane managed?
Is the API endpoint protected?
Is etcd encrypted?
Is TLS enabled?
Are Control Plane logs retained?

Review Phase 3 — Worker Node Architecture

Review:

kubectl get nodes

kubectl describe node <NODE>

Confirm:

Private Nodes
Managed Node Groups
Multiple Availability Zones
Node Labels
Taints
Runtime

Architecture Diagram

Control Plane

↓

Worker Nodes

↓

Pods

↓

Services

Review:

Node sizing
Node lifecycle
Auto Scaling
Patch management

Review Phase 4 — Namespace Design

Review

kubectl get namespaces --show-labels

Confirm separation for:

Production

Development

Testing

Monitoring

Security

Shared Services

Review labels:

owner
application
environment
cost-centre
business-unit

Review Phase 5 — Workload Architecture

Review:

kubectl get deployments -A

Inspect representative deployments.

kubectl describe deployment <DEPLOYMENT>

Confirm:

Replica count
Rolling updates
Resource requests
Resource limits
Health probes
Security contexts

Review workload resilience.

Questions:

Are applications stateless?
Are StatefulSets used correctly?
Are multiple replicas configured?
Can workloads recover automatically?

Review Phase 6 — Networking Architecture

Review:

kubectl get svc -A

kubectl get ingress -A

kubectl get networkpolicy -A

Confirm:

Internal services use ClusterIP
External services are approved
Network Policies exist
TLS is enabled
Ingress Controller is hardened

Architecture

Internet

↓

WAF

↓

Ingress

↓

Service

↓

Pods

Architecture Questions

Is east-west traffic restricted?
Are public endpoints documented?
Is ingress protected?
Are Network Policies implemented?

Review Phase 7 — DNS Architecture

Review:

kubectl get pods -n kube-system -l k8s-app=kube-dns

Test:

kubectl exec dns-test-client -- nslookup kubernetes.default

Confirm:

DNS redundancy
Internal resolution
Service discovery

Review Phase 8 — Storage Architecture

Review:

kubectl get storageclass

kubectl get pv

kubectl get pvc -A

Confirm:

Dynamic Provisioning
Storage Classes
Encryption
Access Modes
Reclaim Policies

Enterprise Storage Example

Application

↓

PVC

↓

Storage Class

↓

Amazon EBS

↓

AWS KMS

Architecture Questions

Is storage encrypted?
Is backup enabled?
Are snapshots taken?
Is storage monitored?

Review Phase 9 — Identity Architecture

Review:

kubectl get serviceaccounts -A

kubectl get clusterroles

kubectl get clusterrolebindings

Confirm:

Dedicated Service Accounts
RBAC
Least Privilege
No excessive cluster-admin usage

Cloud integrations:

AWS IAM Roles for Service Accounts (IRSA)
Azure Managed Identity
Google Workload Identity

Review Phase 10 — Security Architecture

Review workload security.

Look for:

Root containers
Privileged containers
HostPath
Host Network
Host PID
Host IPC

Review:

kubectl get pods -A -o wide

Review security controls:

Security Contexts
Seccomp
Capabilities
Read-only filesystem

Architecture

Identity

↓

RBAC

↓

Admission

↓

Pod Security

↓

Runtime

↓

Monitoring

Review Phase 11 — Secrets Architecture

Review:

kubectl get secrets -A

Confirm:

External Secret Manager
Encryption
Secret Rotation
Least Privilege

Examples:

AWS Secrets Manager
Azure Key Vault
Google Secret Manager
HashiCorp Vault

Review Phase 12 — Observability Architecture

Review monitoring stack.

Examples:

Prometheus
Grafana
Loki
Fluent Bit
OpenTelemetry

Cloud integrations:

Amazon CloudWatch
Azure Monitor
Google Cloud Operations

Confirm:

Metrics
Logs
Alerts
Dashboards

Review Phase 13 — Backup & Disaster Recovery

Review:

etcd backups
PV backups
Recovery testing
Cross-region recovery
Backup frequency

Cloud services:

AWS Backup
Azure Backup
Google Backup

Review Phase 14 — Scalability Review

Confirm:

Cluster Autoscaler
Horizontal Pod Autoscaler
Vertical Pod Autoscaler
Node scaling
Rolling deployments

Questions:

Can the platform scale automatically?
Can workloads survive node failures?
Can the platform recover from AZ failures?

Review Phase 15 — Governance

Review:

Naming standards
Labels
Policies
Documentation
Change management
Platform ownership

Confirm:

Runbooks exist
Incident Response documented
Security reviews completed

Review Phase 16 — Production Readiness

Evaluate:

Area	Status
Architecture
High Availability
Security
Networking
Storage
Identity
Monitoring
Backup
Governance
Documentation

Architecture Risk Matrix

Critical

Examples

Single Control Plane
Public API Server
No RBAC
No backups
Unencrypted Secrets

High

Examples

Single Worker Node
No Network Policies
Containers running as root
Missing monitoring

Medium

Examples

Missing labels
Resource limits absent
Outdated Kubernetes version

Low

Examples

Documentation improvements
Naming inconsistencies
Legacy resources

Architecture Best Practices

Enterprise Kubernetes platforms should provide:

Multi-AZ deployment
Managed Control Plane
Private Worker Nodes
RBAC
Dedicated Service Accounts
Pod Security Standards
Network Policies
Secure Ingress
Encrypted Storage
External Secrets
Continuous Monitoring
Automated Backups
Infrastructure as Code
CI/CD Integration
Disaster Recovery

Architecture Review Checklist

Component	Review Complete
Platform Design	☐
Control Plane	☐
Worker Nodes	☐
Networking	☐
DNS	☐
Storage	☐
Identity	☐
RBAC	☐
Secrets	☐
Monitoring	☐
Logging	☐
Backup	☐
Disaster Recovery	☐
Governance	☐
Operational Readiness	☐

Architecture Decision Matrix

Area	Pass	Observation	Recommendation
Platform Design
Security
Networking
Storage
IAM
Monitoring
Compliance
Scalability
Resilience
Operations

Production Readiness Scorecard

Category	Score (0–5)
High Availability
Security
Networking
Storage
Identity
Monitoring
Backup
Governance
Automation
Documentation

Overall Score

Score	Readiness
45–50	Production Ready
35–44	Conditionally Ready
20–34	Requires Improvement
Below 20	Not Production Ready

Escalation Matrix

Finding Severity	Action
Critical	Escalate immediately to Cloud Platform Architect
High	Escalate to Kubernetes Platform Lead
Medium	Raise engineering improvement task
Low	Record for future optimisation

Architecture Review Report

Platform Name:

Cloud Provider:

Assessment Date:

Reviewer:

Kubernetes Version:

Architecture Summary:

Control Plane:

Worker Nodes:

Networking:

Storage:

Identity:

Security:

Monitoring:

Backup:

Governance:

High Availability:

Scalability:

Critical Findings:

High Findings:

Medium Findings:

Recommendations:

Overall Architecture Status:

Production Approval:

Approved

Conditionally Approved

Rejected

Enterprise Recommendations

Recommended implementation priorities:

Implement Zero Trust networking.
Enforce least-privilege RBAC.
Adopt external secrets management.
Encrypt all persistent storage.
Implement runtime threat detection.
Enable centralised monitoring and logging.
Automate backup validation.
Continuously review platform architecture.

Evidence Collection

Capture evidence for:

Cluster information
Node architecture
Namespace design
Workload architecture
Service architecture
Network Policies
Storage architecture
RBAC
Service Accounts
Monitoring stack
Logging platform
Backup configuration
Production readiness scorecard
Final architecture review report

Runbook Summary

This runbook provides a structured framework for reviewing an enterprise Kubernetes platform from an architectural perspective.

By following this assessment, Kubernetes Security Engineers can validate whether the platform is designed for scalability, resilience, security, governance, and operational excellence. The outcome is a documented architecture review with risk ratings, recommendations, and a production readiness decision that supports Architecture Review Board (ARB) and Change Advisory Board (CAB) approvals.