Agones Minecraft

Minecraft dedicated game server cluster hosting solution using GKE and Agones.

Suitable for both ephemeral and eternal game servers

Current architecture consists of:

• Kubernetes cluster with Agones CRDs and controllers for deploying Minecraft server game pods

• Custom Java and Bedrock Minecraft server kubernetes pods specs with sidecar services for health checking, auto world backup and, auto world loading

• Controller managed DNS zone for auto provisioning custom DNS A and SRV records for Minecraft servers

Terraform

Prerequisites

• a GCP project

• a domain you own or manage

• gcloud

• kubectl

• terraform >= 0.15.0

Get default credentials for project to use with Terraform

gcloud auth application-default login

Enable services for GKE, Cloud DNS, and Cloud Storage

gcloud services enable compute.googleapis.com container.googleapis.com dns.googleapis.com storage-component.googleapis.com

Change tf variables if needed

nano terraform/terraform.tfvars

Variables

• region

  • string
  • Cluster VPC region

• zone

  • string
  • Cluster zone

• storage_location

  • string
  • GCS storage location

• agones_version

  • string
  • Agones helm chart version

• cluster_version

  • string
  • Kubernetes master and node version (set to 1.18.18 as recommended by Agones)

• auto_scaling

  • bool
  • enable node auto scaling. Only recommended for strictly ephemeral game server clusters

• min_node_count

  • number
  • minimum node count for auto scaling

• max_node_count

  • number
  • maximum node count for auto scaling

Run

The following Terraform configuration will provision:

• A 2 n2-standard-4 (4 x vCPU, 16GB RAM) node zonal us-central1-a GKE cluster (with optional auto scaling)

• A Custom us-central1 VPC network

• Firewall rules for TCP and UDP traffic on ports 7000-8000 from anywhere for cluster nodes

• A Multi-regional us storage bucket for Minecraft world archives

• A DNS zone for an owned or managed domain

• Agones Helm chart installation with an HTTP ping service behind a cluster provisioned GCP Load Balancer

• An ExternalDNS controller deployment for DNS record management

Command will run terraform init, plan, and apply.

make tf

Inputs

Terraform CLI will ask for inputs for your domain and GCP project ID

# Example

var.dns_name
  managed dns zone name

  Enter a value: example.com.

var.project_id
  gcp project id

  Enter a value: agones-minecraft-xxxxx

Outputs

Outputs will include the name servers for your DNS zone. Configure your domain to point to these name servers

# Example

Outputs:

name_servers = tolist([
  "ns-cloud-e1.googledomains.com.",
  "ns-cloud-e2.googledomains.com.",
  "ns-cloud-e3.googledomains.com.",
  "ns-cloud-e4.googledomains.com.",
])

Manual Installation

Prerequisites

• gcloud

• kubectl

• A GCP project

• a domain you own or manage

• terraform >= 0.15.0

1. Create public DNS Zone

This public DNS zone will be used to assign A and SRV DNS record to Minecraft GameServers

gcloud dns managed-zones create agones-minecraft \
    --description="externalDNS managed DNS zone" \
    --dns-name=<DOMAIN> \
    --visibility=public

Point an owned domain to the zone's NS record. This is done on the domain name registrar.

gcloud dns managed-zones describe agones-minecraft

2. Create backup storage bucket

World archives will be storage on GCP Cloud Storage buckets. Object storage offers better portability, easier management, and an overall better price over volumes.

The following command will make a multi-region bucket named agones-minecraft-mc-worlds in the us. In GCS, bucket names must be globally unique so use a different name. Since bucket creation rate limited to 1 every 2 seconds, A single bucket containing all backups will be made.

gsutil mb -l us gs://agones-minecraft-mc-worlds

3. Create Kubernetes Cluster

Creates GKE cluster with 2 n2-standard-4 (4 x vCPU, 16GB RAM), tags for firewall, and necessary scopes for Cloud DNS and Cloud Storage

gcloud container clusters create minecraft --cluster-version=1.18 \
  --tags=mc \
  --scopes=gke-default,storage-rw,"https://www.googleapis.com/auth/ndev.clouddns.readwrite" \
  --num-nodes=2 \
  --no-enable-autoupgrade \
  --machine-type=n2-standard-4

Optionally, for strictly ephemeral game servers, you can enable node autoscaling

gcloud container clusters create minecraft --cluster-version=1.18 \
  --tags=mc \
  --scopes=gke-default,storage-rw,"https://www.googleapis.com/auth/ndev.clouddns.readwrite" \
  --num-nodes=2 \
  --no-enable-autoupgrade \
  --machine-type=n2-standard-4 \
  --enable-autoscaling

Set cluster as default and get credentials for kubectl

gcloud config set container/cluster minecraft
gcloud container clusters get-credentials minecraft

4. Add Firewall rules

Players will connect to GameServer Pods using controller allocated hostPorts. Assign firewall rules to open all Agones allocatable ports. TCP is for Java and UDP is for Bedrock servers

gcloud compute firewall-rules create mc-server-firewall \
  --allow tcp:7000-8000,udp:7000-8000 \
  --target-tags mc \
  --description "Firewall rule to allow mc server tcp traffic"

5. Install Agones

kubectl create namespace agones-system
kubectl apply -f https://raw.githubusercontent.com/googleforgames/agones/release-1.14.0/install/yaml/install.yaml

or

helm repo add agones https://agones.dev/chart/stable
helm repo update
helm install agones --namespace agones-system --create-namespace agones/agones

6. Verify Agones Installation

kubectl get pods -n agones-system

7. Install ExternalDNS

Controller Documentation

This controller is a fork of kubernetes-sigs/external-dns custom support for Agones GameServer sources. It will manage A and SRV records for Agones GameServers and Fleets allowing players to connect using a unique subdomain.

kubectl apply -f https://raw.githubusercontent.com/saulmaldonado/agones-minecraft/main/k8s/external-dns.yml

Deploy Java Servers

1. Deploy Minecraft GameServer Fleet

Fleets will deploy and manage a set of Ready GameServers that can immediately be allocated for players to connect to.

# replace 'example.com' with the domain of the managed zone

sed 's/<DOMAIN>/example.com/' k8s/mc-server-fleet.yml | kubectl apply -f -

Full Java server fleet example

2. Allocate a Ready Server

Allocating a server will make sure it does not get shutdown in the event of fleet scaling or rolling restart.

kubectl create -f k8s/allocation.yml

3. Connect to Java Server

Players can connect using unique subdomain

<GAMESERVER_NAME>.<MANAGED_ZONE_DOMAIN>

example:

NAME             STATE       ADDRESS       PORT   NODE
mc-dj4jq-52tsd   Allocated   35.232.46.5   7701   gke-minecraft-default-pool-47e5fdf8-5h9q

external-dns.alpha.kubernetes.io/hostname: saulmaldonado.me.

mc-dj4jq-52tsd.saulmaldonado.me

Deploy Bedrock Servers

1. Deploy Bedrock GameServer Fleet

Fleets will deploy and manage a set of Ready GameServers that can immediately be allocated for players to connect to.

# replace 'example.com' with the domain of the managed zone

sed 's/<DOMAIN>/example.com/' k8s/mc-bedrock-fleet.yml | kubectl apply -f -

Full Bedrock server fleet example

2. Allocate a Ready Bedrock Servers

Allocating a server will make sure it does not get shutdown in the event of fleet scaling or rolling restart.

kubectl create -f k8s/bedrock-allocation.yml

3. Connect to Bedrock Server

Players can connect using unique subdomain and allocated port (bedrock does not support SRV records)

<GAMESERVER_NAME>.<MANAGED_ZONE_DOMAIN>:<GAMESERVER_PORT>

example:

NAME             STATE       ADDRESS       PORT   NODE
mc-dj4jq-52tsd   Allocated   35.232.46.5   7701   gke-minecraft-default-pool-47e5fdf8-5h9q

external-dns.alpha.kubernetes.io/hostname: saulmaldonado.me.

address: mc-dj4jq-52tsd.saulmaldonado.me
port: 7701