Kubernetes cluster networking template

Components in this network diagram

• Internet client
• Cloud load balancer
• NGINX ingress controller
• Service: frontend ClusterIP
• Service: api ClusterIP
• kube-proxy iptables / IPVS rules
• frontend pod: node 1
• frontend pod: node 2
• api pod: node 1
• api pod: node 2
• Calico CNI: pod CIDR & routing
• CoreDNS service discovery
• NetworkPolicy allows egress?
• Service: postgres headless
• Packet dropped
• PostgreSQL StatefulSet
• NAT gateway egress
• External APIs

How to use this network diagram template

1. Click Open in the editor. The network diagram opens on a new page in FlowDiagram — nothing is uploaded and there is no sign-up.
2. Rename, add or delete shapes and drag them where you want; connectors stay attached as things move.
3. Drop in vendor logos from the library — 1,160 of them, including every AWS, Azure and Google Cloud service icon — or restyle it with the colour and theme controls.
4. Prefer text? Edit the Mermaid source below and paste it in through ☰ → Import diagram (see the Mermaid editor); it imports as an editable diagram.
5. Export to PNG, SVG or PDF, or press Ctrl+L for a link that carries the whole diagram.

Mermaid source

The whole template is the text below. Paste it into FlowDiagram, keep it in Git next to the code it describes, or hand it to an AI assistant to extend.

flowchart TD
  CLIENT((Internet client)) --> LB[Cloud load balancer]
  LB --> ING[NGINX ingress controller]
  ING --> SVCA[Service: frontend ClusterIP]
  ING --> SVCB[Service: api ClusterIP]
  SVCA --> KP[kube-proxy iptables / IPVS rules]
  SVCB --> KP
  KP --> PODA1[frontend pod: node 1]
  KP --> PODA2[frontend pod: node 2]
  KP --> PODB1[api pod: node 1]
  KP --> PODB2[api pod: node 2]
  CNI[Calico CNI: pod CIDR & routing] -.-> PODA1
  CNI -.-> PODB2
  PODA1 --> DNS[CoreDNS service discovery]
  DNS --> SVCB
  PODB1 --> NP{NetworkPolicy allows egress?}
  PODB2 --> NP
  NP -->|Yes| DBSVC[Service: postgres headless]
  NP -->|No| DROP[Packet dropped]
  DBSVC --> DB[(PostgreSQL StatefulSet)]
  PODB1 --> EGRESS[NAT gateway egress]
  EGRESS --> EXT((External APIs))

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