kubernetes-homelab

A repository to keep resources and configuration files used with my Kubernetes homelab.

Quick Links

1. Content of the Repository
2. Homelab Network Diagram
3. Network Configuration
4. Homelab Infrastructure
   • Hardware
   • Guest Provisioning
   • Shared Storage
   • Other Services
   • Kubernetes Cluster Configuration
   • Backups
   • Homelab Root CA
   • Average Power Consumption
5. Deployment
   • Ansible-defined Kubernetes Homelab
   • Manage Kubernetes Homelab with Terraform
   • Manage Kubernetes Homelab Manually
   • Install Istio
6. Upgrades
7. Blog Posts
8. Stargazers Over Time

Content of the Repository

• ansible - Ansible playbooks to deploy Kubernetes homelab.
• cka - CKA study notes.
• ckad - CKAD study notes.
• kubernetes - Kubernetes resources that are defined in YAML and to be deployed using kubectl.
• kubernetes/helm - Kubernetes resources to be deployed using helm charts.
• packer - configuration files build Qemu/KVM images with Packer.
• pxe - configuration files for PXE boot and Kickstart.
• regcred - docker registry credentials.
• terraform - configuration files to manage Kubernetes with Terraform.

Homelab Network Diagram

Network Configuration

Network is configured as follows:

• LAN: 10.11.1.0/24.
• Gateway: 10.11.1.1.
• DNS/DHCP/NTP/SMTP servers: 10.11.1.2 and 10.11.1.3.
• Managed switch: 10.11.1.4 currently no special config but a couple of VLANs to separate homelab devices from the rest of the home network.
• PXE boot server: 10.11.1.20.
• DNS private zone: hl.test (a reserved top level DNS name .test, see rfc2606).
• DHCP: range 10.11.1.140-10.11.1.149.

Hostnames and their IP addresses:

Hostname	IP Address	Information	OS
mikrotik.hl.test	10.11.1.1	Mikrotik router	RouterOS
admin1.hl.test	10.11.1.2	DNS/DHCP master, NTP, SMTP, HAProxy master, Keepalived	Rocky 8
admin2.hl.test	10.11.1.3	DNS/DHCP slave, NTP, SMTP, HAProxy backup, Keepalived	Rocky 8
switch.hl.test	10.11.1.4	Managed switch	N/A
truenas.hl.test	10.11.1.5	TrueNAS Core shared storage server for Kubernetes	TrueNAS Core 12
pi.hl.test	10.11.1.7	RaspberryPi Pi-hole DNS ad blocker	Raspbian
mikrotik-lte.hl.test	10.11.1.11	Mikrotik wireless access point with LTE antennas	RouterOS
pxe.hl.test	10.11.1.20	PXE boot server	Rocky 8
kvm1.hl.test	10.11.1.21	KVM hypervisor	Rocky 8
kvm2.hl.test	10.11.1.22	KVM hypervisor	Rocky 8
kvm3.hl.test	10.11.1.23	KVM hypervisor	Rocky 8
kubelb.hl.test	10.11.1.30	Virtual IP address for HAProxy/keepalived	N/A
srv31.hl.test	10.11.1.31	Kubernetes control plane	Rocky 9
srv32.hl.test	10.11.1.32	Kubernetes control plane	Rocky 9
srv33.hl.test	10.11.1.33	Kubernetes control plane	Rocky 9
srv34.hl.test	10.11.1.34	Kubernetes worker node	Rocky 9
srv35.hl.test	10.11.1.35	Kubernetes worker node	Rocky 9
srv36.hl.test	10.11.1.36	Kubernetes worker node	Rocky 9

Homelab Infrastructure

Kubernetes environment runs on three KVM hypervisors. The goal is to maintain service in the event of a loss of a (single) host. This blog post explains how to build a multi-master Kubernetes homelab cluster by hand using KVM, PXE boot and kubeadm.

Hardware

Commodity hardware is used to keep costs to a minimum.

Hostname	CPU Cores	RAM (MB)	Storage	OS
pxe.hl.test	4	8192	120GB SSD	Rocky 8
kvm1.hl.test	8	24576	240GB SSD	Rocky 8
kvm2.hl.test	8	24576	240GB SSD	Rocky 8
kvm3.hl.test	8	24576	240GB SSD	Rocky 8
truenas.hl.test	4	8192	240GB SSD, 2x 320GB HDDs in RAID 1 for storage pool	TrueNAS Core 12
mikrotik.hl.test	1	128	128MB	RouterOS
pi.hl.test	1	512	8GB	Raspbian

Guest Provisioning

Previously, provisioning of KVM guests was done by using a PXE boot server with Kickstart templates.

I have since migrated to Packer to make the VM deployment process faster. PXE boot is still used to provision physical hosts (hypervisors).

Shared Storage

A TrueNAS NFS server is used to create persistent volumes claims using democratic-csi.

Other Services

Homelab provides other services to Kubernetes that aren't covered here:

• Bind DNS servers with failover and dynamic updates
• DHCP failover with dynamic DNS
• Peered NTP servers
• Redundant SMTP relays

Backups

Velero is used to safely backup and restore Kubernetes cluster resources and persistent volumes.

Kubernetes Cluster Configuration

Component	Software
CNI	Calico
CRI	Containerd
CSI	Democratic CSI
DNS	CoreDNS
Load Balancer	MetalLB
Service Mesh	Istio

Homelab Root CA

SSL certificates are signed by the homelab CA.

Create your own Certificate Authority (CA) for homelab environment. Run the following on Linux:

openssl req -newkey rsa:2048 -keyout homelab-ca.key -nodes -x509 -days 3650 -out homelab-ca.crt

Create a Kubernetes Wildcard Cert Signed by the Root CA

DOMAIN=wildcard.apps.hl.test
openssl genrsa -out "${DOMAIN}".key 2048 && chmod 0600 "${DOMAIN}".key
openssl req -new -sha256 -key "${DOMAIN}".key -out "${DOMAIN}".csr
openssl x509 -req -in "${DOMAIN}".csr -CA homelab-ca.crt -CAkey homelab-ca.key -CAcreateserial -out "${DOMAIN}".crt -days 1825 -sha256

Average Power Consumption

~170W

Monthly, the homelab costs (((170W * 24h) / 1000) * £0.33/kWh * 365days) / 12months = £40.95 (~47$).

Deployment

The deployment section assumes that the homelab environment has been provisioned.

Ansible-defined Kubernetes Homelab

See ansible/README.md.

Use this to deploy Kubernetes cluster with Ansible.

Manage Kubernetes Homelab with Terraform

See terraform/README.md.

Use this to deploy various Kubernetes resources with Terraform.

Manage Kubernetes Homelab Manually

Install democratic-csi Shared Storage Driver

Democratic CSI implements the container storage interface spec providing storage for Kubernetes.

helm repo add democratic-csi https://democratic-csi.github.io/charts/
helm repo update

helm upgrade --install zfs-nfs \
  democratic-csi/democratic-csi \
  --namespace democratic-csi \
  --create-namespace \
  --version "0.11.1" \
  --values ./kubernetes/helm/truenas-nfs/freenas-nfs.yaml

Install MetalLB

Update the config map kubernetes/metallb/metallb-config-map.yml and specify the IP address range. Deploy MetalLB network load-balancer:

kubectl apply -f ./kubernetes/metallb

Install Istio

The Istio namespace must be created manually.

kubectl create ns istio-system

The kubectl apply command may show transient errors due to resources not being available in the cluster in the correct order. If that happens, simply run the command again.

kubectl apply -f ./kubernetes/istio/istio-kubernetes.yml

Install httpd-healthcheck:

kubectl apply -f ./kubernetes/httpd-healthcheck

Install Istio add-on Prometheus:

kubectl apply -f ./kubernetes/istio-addons/prometheus

Install Istio add-on Kiali:

kubectl apply -f ./kubernetes/istio-addons/kiali

Create Monitoring Namespace

kubectl apply -f ./kubernetes/monitoring-ns-istio-injection-enabled.yml
kubectl apply -f ./kubernetes/monitoring-ns-with-istio

Install kube-state-metrics

Deploy kube-state-metrics:

kubectl apply -f ./kubernetes/kube-state-metrics

Install Prometheus

Create a secret called prometheus-cluster-name that contains the cluster name the Prometheus instance is running in:

kubectl -n monitoring create secret generic \
  prometheus-cluster-name --from-literal=CLUSTER_NAME=kubernetes-homelab

Deploy prometheus:

kubectl apply -f ./kubernetes/prometheus

Install Grafana

kubectl apply -f ./kubernetes/grafana

Install Alertmanager

Alertmanager uses the Incoming Webhooks feature of Slack, therefore you need to set it up if you want to receive Slack alerts.

Update the config map kubernetes/alertmanager/alertmanager-config-map.yml and specify your incoming webhook URL. Deploy alertmanager:

kubectl apply -f ./kubernetes/alertmanager

Install Mikrotik-exporter

Update the secret file kubernetes/mikrotik-exporter/mikrotik-exporter-secret.yml and specify your password for the Mikrotik API user. Deploy mikrotik-exporter:

kubectl apply -f ./kubernetes/mikrotik-exporter

Install Pi-hole Exporter

kubectl apply -f ./kubernetes/pihole-exporter

Install X509 Certificate Exporter

Deploy the Helm chart:

helm repo add enix https://charts.enix.io

helm install x509-certificate-exporter \
  enix/x509-certificate-exporter \
  --namespace monitoring \
  --version "1.20.0" \
  --values ./kubernetes/helm/x509-certificate-exporter/values.yml

Install Kubecost

kubectl create namespace kubecost

helm repo add kubecost https://kubecost.github.io/cost-analyzer/

helm upgrade --install kubecost \
  kubecost/cost-analyzer \
  --namespace kubecost \
  --version "1.91.2" \
  --values ./kubernetes/helm/kubecost/values.yaml

kubectl apply -f ./kubernetes/helm/kubecost/kubecost-service.yaml

Install Loki and Promtail

kubectl create namespace logging
kubectl apply -f ./kubernetes/logging/loki-pvc.yml
kubectl apply -f ./kubernetes/logging/loki-deployment.yml
kubectl apply -f ./kubernetes/logging/promtail-deployment.yml

Upgrades

• Upgrading Kubernetes from 1.24 to 1.25
• Upgrading Kubernetes from 1.23 to 1.24
• Upgrading Kubernetes from 1.22 to 1.23
• Upgrading Kubernetes from 1.21 to 1.22
• Upgrading Kubernetes from 1.20 to 1.21
• Upgrading Kubernetes from 1.19 to 1.20

Blog Posts

• Install and Configure a Multi-Master HA Kubernetes Cluster with kubeadm, HAProxy and Keepalived on CentOS 7
• Create Your Own Certificate Authority (CA) for Homelab Environment
• Install Kubernetes Dashboard
• Install Kube State Metrics on Kubernetes
• Install and Configure Prometheus Monitoring on Kubernetes
• Install and Configure Grafana on Kubernetes
• Install and Configure Alertmanager with Slack Integration on Kubernetes
• Monitor Etcd Cluster with Grafana and Prometheus
• Monitor Bind DNS Server with Grafana and Prometheus (bind_exporter)
• Monitor HAProxy with Grafana and Prometheus (haproxy_exporter)
• Monitor Linux Servers with Grafana and Prometheus (node_exporter)
• Monitor Mikrotik Router with Grafana and Prometheus (mikrotik-exporter)
• Install MetalLB and Istio Ingress Gateway with Mutual TLS for Kubernetes
• Moving to TrueNAS and Democratic CSI for Kubernetes Persistent Storage
• Configure PXE Boot Server for Rocky Linux 8 Kickstart Installation
• Migrating HA Kubernetes Cluster from CentOS 7 to Rocky Linux 8
• Blue/Green Deployment with Istio: Match Host Header and sourceLabels for Pod to Pod Communication
• Install Kubecost to Help Optimise Kubernetes Applications
• Speedtest with InfluxDB and Grafana on Kubernetes
• OpenVPN Server on Kubernetes
• Building Qemu KVM Images with Packer
• Deploy Elasticsearch and Kibana on Kubernetes with Helm
• Backup Kubernetes Cluster Resources to AWS S3 with Velero
• Replacing a Failed Control Plane Node in a HA Kubernetes Cluster

Stargazers Over Time