MetalLB Setup¶

In a standard cloud Kubernetes setup, creating a Service of type LoadBalancer automatically provisions a cloud load balancer with a public IP. On bare-metal, no such mechanism exists out of the box. MetalLB fills this gap by assigning real IP addresses from your local subnet to LoadBalancer services.

Prerequisites

All master and worker nodes are up and joined to the cluster
You have a range of free IP addresses on your local subnet (not assigned by DHCP)
Commands are run from a master node

Step 1 — Install MetalLB¶

Apply the official MetalLB manifest from a master node:

kubectl apply -f https://raw.githubusercontent.com/metallb/metallb/v0.15.3/config/manifests/metallb-native.yaml

This creates the metallb-system namespace and deploys the MetalLB controllers.

Step 2 — Configure an IP Address Pool¶

Create a file named metallb-config.yaml. Choose a free IP range from your router's subnet that is not part of the DHCP pool.

metallb-config.yaml

apiVersion: metallb.io/v1beta1
kind: IPAddressPool
metadata:
  name: external-ip-pool
  namespace: metallb-system
spec:
  addresses:
  - 192.168.0.170-192.168.0.175
---
apiVersion: metallb.io/v1beta1
kind: L2Advertisement
metadata:
  name: l2-advert
  namespace: metallb-system

Choose your IP range carefully

IPs in the pool (e.g. 192.168.0.170–192.168.0.175) must not be assigned by your router's DHCP server, otherwise you'll get IP conflicts. Reserve them in your router's DHCP settings if possible.

Step 3 — Apply the Configuration¶

sudo kubectl apply -f metallb-config.yaml

Verification¶

After applying, any Service of type LoadBalancer will automatically get an IP from the pool:

sudo kubectl get svc -o wide

You should see an EXTERNAL-IP assigned from your configured range (e.g. 192.168.0.170).

Next Step

Validate your full setup by deploying a test pod and service.