A node port is a built-in feature that allows users to access a service from the IP of any k8s node using a static port. The main drawback of using node ports is that your port must be in the range 30000-32767 and that there can, of course, be no overlapping node ports among services. Using node ports also forces you to expose your k8s nodes to users who need to access your services, which could pose security risks.

MetalLB is a third-party load balancer implementation for bare metal servers. A load balancer exposes a service on an IP external to your k8s cluster at any port of your choosing and routes those requests to yours k8s nodes.