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MetalLB — Real LoadBalancer IPs on Bare-Metal

On cloud providers (AWS, GCP, Azure) when you create a Kubernetes Service of type LoadBalancer, the cloud automatically provisions a load balancer with a real IP. On bare-metal, this does nothing — services stay in <pending> state forever.

MetalLB fixes this by assigning real IPs from your local network to LoadBalancer services.

How It Works​

kubectl expose deployment my-app --type=LoadBalancer --port=80
        │
        ▼
MetalLB assigns: 10.0.0.200
        │
        ▼
Any machine on 10.0.0.0/24 can reach:
http://10.0.0.200:80  → my-app

MetalLB announces the IP via ARP (Layer 2 mode) so the network switch routes traffic correctly.

Install MetalLB​

kubectl apply -f https://raw.githubusercontent.com/metallb/metallb/v0.14.5/config/manifests/metallb-native.yaml

Wait for pods:

kubectl get pods -n metallb-system --watch

Configure IP Address Pool​

Define a range of IPs MetalLB can hand out — these must be in your 10.0.0.0/24 subnet and not assigned to anything else:

apiVersion: metallb.io/v1beta1
kind: IPAddressPool
metadata:
  name: cluster-pool
  namespace: metallb-system
spec:
  addresses:
    - 10.0.0.200-10.0.0.250
---
apiVersion: metallb.io/v1beta1
kind: L2Advertisement
metadata:
  name: cluster-l2
  namespace: metallb-system
spec:
  ipAddressPools:
    - cluster-pool
kubectl apply -f metallb-config.yaml

Test It​

kubectl create deployment nginx --image=nginx
kubectl expose deployment nginx --type=LoadBalancer --port=80
kubectl get svc nginx

Expected output:

NAME    TYPE           CLUSTER-IP     EXTERNAL-IP    PORT(S)
nginx   LoadBalancer   10.96.12.34    10.0.0.200     80:31234/TCP

EXTERNAL-IP is no longer <pending> — it has a real IP.

curl http://10.0.0.200
# → nginx welcome page

Via Tailscale (subnet route advertised), this works from any remote machine too.

Assigned IP Pool Plan​

RangeUse
10.0.0.1MAAS Controller
10.0.0.2–10.0.0.10Cluster nodes (MAAS DHCP)
10.0.0.200–10.0.0.250MetalLB LoadBalancer pool

Done When​

✔ MetalLB pods Running
✔ IPAddressPool and L2Advertisement applied
✔ LoadBalancer service gets a 10.0.0.200+ IP
✔ Service reachable directly by IP