Kubernetes,
networking and everything around it...
A private collection of notes, guides and technical experiments — primarily on Kubernetes, networking and related topics
Cluster Status
Status hentes…
Nodes
Setup
flowchart LR
subgraph LAN["LAN clients"]
C["Workstations / kubectl / browser"]
end
subgraph GITOPS["GitOps"]
GH[("GitHub
s3-2020/k3s-gitops")] --> FL["Flux"] end subgraph K3S["K3s cluster · Embedded etcd"] TR["Traefik Gateway API
10.22.50.60 · Cilium L2"] VIP["Keepalived VIP 10.22.50.120
:6443 → k3s on the VIP owner"] K1["k1
10.22.50.121"] K2["k2
10.22.50.122"] K3["k3
10.22.50.123"] TR --> K1 & K2 & K3 VIP -.->|"VIP owner answers"| K1 VIP -.->|"failover"| K2 & K3 end C -->|"API :6443"| VIP C -->|"https://*.kung.dk"| TR FL -->|"reconcile (SSH)"| K1 & K2 & K3 classDef box fill:#e8f4ff,stroke:#68aef5,color:#064b8e,stroke-width:1.2px class C,VIP,TR,GH,FL,K1,K2,K3 box style LAN fill:transparent,stroke:transparent style GITOPS fill:transparent,stroke:transparent style K3S fill:transparent,stroke:transparent linkStyle default stroke:#7895b1,stroke-width:1.2px
s3-2020/k3s-gitops")] --> FL["Flux"] end subgraph K3S["K3s cluster · Embedded etcd"] TR["Traefik Gateway API
10.22.50.60 · Cilium L2"] VIP["Keepalived VIP 10.22.50.120
:6443 → k3s on the VIP owner"] K1["k1
10.22.50.121"] K2["k2
10.22.50.122"] K3["k3
10.22.50.123"] TR --> K1 & K2 & K3 VIP -.->|"VIP owner answers"| K1 VIP -.->|"failover"| K2 & K3 end C -->|"API :6443"| VIP C -->|"https://*.kung.dk"| TR FL -->|"reconcile (SSH)"| K1 & K2 & K3 classDef box fill:#e8f4ff,stroke:#68aef5,color:#064b8e,stroke-width:1.2px class C,VIP,TR,GH,FL,K1,K2,K3 box style LAN fill:transparent,stroke:transparent style GITOPS fill:transparent,stroke:transparent style K3S fill:transparent,stroke:transparent linkStyle default stroke:#7895b1,stroke-width:1.2px
Nodes
Masters only setup
| Node | Internal IP | Roles | Status | Kubernetes | OS | Runtime |
|---|---|---|---|---|---|---|
| k1 | 10.22.50.121/24 | control-plane, etcd | Ready | v1.36.4+k3s1 | Ubuntu 26.04 | containerd 2.3.4-k3s1 |
| k2 | 10.22.50.122/24 | control-plane, etcd | Ready | v1.36.4+k3s1 | Ubuntu 26.04 | containerd 2.3.4-k3s1 |
| k3 | 10.22.50.123/24 | control-plane, etcd | Ready | v1.36.4+k3s1 | Ubuntu 26.04 | containerd 2.3.4-k3s1 |
Verified with "kubectl get nodes -o wide".
Embedded etcd with 3 members, quorum = 2.
k1 is cluster-init bootstrap-node.
No agent-only nodes.
Node Builds
Hardware
| Node | CPU | Cores / threads | RAM |
|---|---|---|---|
| k1 | Intel i7-8700 @ 3.20 GHz | 12 vCPU (= 6C / 12T, full chip) | ~16 GB |
| k2 | Intel i7-7700 @ 3.60 GHz | 8 vCPU (= 4C / 8T, full chip) | ~16 GB |
| k3 | Intel i7-7700 @ 3.60 GHz | 8 vCPU (= 4C / 8T, full chip) | ~16 GB |