Network Architecture

Network Overview

graph TD
    subgraph External
        Internet((Internet))
        DNS((DNS))
    end

    subgraph Network Edge
        FW[Firewall]
        LB[Load Balancer]
        Internet --> FW
        DNS --> FW
        FW --> LB
    end

    subgraph Kubernetes Network
        subgraph Ingress
            LB --> Traefik[Traefik]
            Traefik --> Services[Internal Services]
        end

        subgraph Network Policies
            Services --> Apps[Applications]
            Services --> DBs[Databases]
        end

        subgraph CNI[Container Network]
            Apps --> Pod1[Pod Network]
            DBs --> Pod1
        end
    end

Components

Ingress Controller

• Traefik: Main ingress controller
  • SSL/TLS termination
  • Automatic certificate management
  • Route configuration
  • Load balancing

Network Policies

graph LR
    subgraph Policies
        Default[Default Deny]
        Allow[Allowed Routes]
    end

    subgraph Apps
        Media[Media Stack]
        Monitor[Monitoring]
        DB[Databases]
    end

    Allow --> Media
    Allow --> Monitor
    Default --> DB

DNS Configuration

• External DNS for automatic DNS management
• Internal DNS resolution
• Split DNS configuration

Security

Network Policies

apiVersion: networking.k8s.io/v1
kind: NetworkPolicy
metadata:
  name: default-deny
spec:
  podSelector: {}
  policyTypes:
  - Ingress
  - Egress

TLS Configuration

• Automatic certificate management via cert-manager
• Let's Encrypt integration
• Internal PKI for service mesh

Service Mesh

Traffic Flow

graph LR
    subgraph Ingress
        External[External Traffic]
        Traefik[Traefik]
    end

    subgraph Services
        App1[Service 1]
        App2[Service 2]
        DB[Database]
    end

    External --> Traefik
    Traefik --> App1
    Traefik --> App2
    App1 --> DB
    App2 --> DB

Best Practices

1. Security

   • Implement default deny policies
   • Use TLS everywhere
   • Regular security audits
   • Network segmentation

2. Performance

   • Load balancer optimization
   • Connection pooling
   • Proper resource allocation
   • Traffic monitoring

3. Reliability

   • High availability configuration
   • Failover planning
   • Backup routes
   • Health checks

4. Monitoring

   • Network metrics collection
   • Traffic analysis
   • Latency monitoring
   • Bandwidth usage tracking

Troubleshooting

Common network issues and resolution steps:

1. Connectivity Issues

   • Check network policies
   • Verify DNS resolution
   • Inspect service endpoints
   • Review ingress configuration

2. Performance Problems

   • Monitor network metrics
   • Check for bottlenecks
   • Analyze traffic patterns
   • Review resource allocation