load-balancing.md

Set up HTTP load balancing on Packet

Introduction

Kubernetes passes on the responsibility of creating a load balancer for services of type LoadBalancer to the underlying cloud provider. Bare metal providers such as Packet, however, typically don't have an implementation of network load-balancers. Therefore, these services always remain in the Pending state forever.

MetalLB aims to address this problem by offering a load balancer implementation for bare metal Kubernetes clusters using standard routing protocols.

Contour, on the other hand, addresses the need for an efficient and smooth ingress traffic management at the Layer 7 level.

Contour is an Ingress controller for Kubernetes that works by deploying the Envoy proxy as a reverse proxy and load balancer.

This guide provides installation steps to configure MetalLB and Contour to help you set up HTTP load balancing on a Lokomotive cluster with Packet Provider.

Learning Objectives

This guide assumes familiarity with Kubernetes and has a basic understanding of Ingress and Load Balancers.

Upon completion of this guide, you will be able to use Service type LoadBalancer in your Lokomotive cluster on Packet.

Prerequisites

To set up HTTP load balancing, we need the following:

• A Lokomotive cluster accessible via kubectl deployed on Packet.

• IPv4 address pools for MetalLB to allocate — one address per LoadBalancer Service. You'll need to request a Public IPv4 from Packet in your intented Location and Packet Project in the Packet UI.

Estimated Time

This how-to guide is expected to take about 15 minutes.

Steps

Step 1: Configure MetalLB and Contour

MetalLB and Contour are available as a Lokomotive components. A configuration file is needed to install them.

MetalLB operates in two modes: BGP and Layer 2. Lokomotive supports MetalLB in BGP mode.

Create a file named ingress.lokocfg with the below contents.

# MetalLB component configuration.
component "metallb" {
  address_pools = {
    default = ["a.b.c.d/X"]
  }
}

# Contour component configuration.
component "contour" {}

Step 2: Install MetalLB and Contour

To install, execute:

lokoctl component install

MetalLB installs in metallb-system namespace, whereas Contour installs in projectcontour namespace.

In few minutes pods from MetalLB and Contour are in Running state.

To verify that the BGP sessions are established, check the logs of the MetalLB speaker pods:

kubectl -n metallb-system logs speaker-89764
...
{"caller":"bgp.go:63","event":"sessionUp","localASN":65000,"msg":"BGP session established","peer":"10.88.72.128:179","peerASN":65530,"ts":"2019-09-17T13:10:43.194650355Z"}

Contour service has an external IP address if it is properly set up with MetalLB.

kubectl get svc envoy -n projectcontour
NAME      TYPE           CLUSTER-IP    EXTERNAL-IP      PORT(S)                      AGE
envoy     LoadBalancer   10.3.101.86   1XX.7X.XX9.XXX   80:30511/TCP,443:32317/TCP   5m