Google Kubernetes Engine

Follow these steps to create a Google Kubernetes Engine (GKE) cluster for your Agones install.

Before you begin

Take the following steps to enable the Kubernetes Engine API:

  1. Visit the Kubernetes Engine page in the Google Cloud Platform Console.
  2. Create or select a project.
  3. Wait for the API and related services to be enabled. This can take several minutes.
  4. Enable billing for your project.
    • If you are not an existing GCP user, you may be able to enroll for a $300 US Free Trial credit.

Choosing a shell

To complete this quickstart, we can use either Google Cloud Shell or a local shell.

Google Cloud Shell is a shell environment for managing resources hosted on Google Cloud Platform (GCP). Cloud Shell comes preinstalled with the gcloud and kubectl command-line tools. gcloud provides the primary command-line interface for GCP, and kubectl provides the command-line interface for running commands against Kubernetes clusters.

If you prefer using your local shell, you must install the gcloud and kubectl command-line tools in your environment.

Cloud shell

To launch Cloud Shell, perform the following steps:

  1. Go to Google Cloud Platform Console
  2. From the top-right corner of the console, click the Activate Google Cloud Shell button: cloud shell
  3. A Cloud Shell session opens inside a frame at the bottom of the console. Use this shell to run gcloud and kubectl commands.
  4. Set a compute zone in your geographical region with the following command. The compute zone will be something like us-west1-a. A full list can be found here.

    gcloud config set compute/zone [COMPUTE_ZONE]

Local shell

To install gcloud and kubectl, perform the following steps:

  1. Install the Google Cloud SDK, which includes the gcloud command-line tool.
  2. Initialize some default configuration by running the following command.

    • When asked Do you want to configure a default Compute Region and Zone? (Y/n)?, enter Y and choose a zone in your geographical region of choice.

      gcloud init
  3. Install the kubectl command-line tool by running the following command:

    gcloud components install kubectl

Creating the cluster

A cluster consists of at least one cluster master machine and multiple worker machines called nodes: Compute Engine virtual machine instances that run the Kubernetes processes necessary to make them part of the cluster.

gcloud container clusters create [CLUSTER_NAME] --cluster-version=1.15 \
  --tags=game-server \
  --scopes=gke-default \
  --num-nodes=4 \
  --no-enable-autoupgrade \
  --machine-type=n1-standard-4

Flag explanations:

  • cluster-version: Agones requires Kubernetes version 1.15.
  • tags: Defines the tags that will be attached to new nodes in the cluster. This is to grant access through ports via the firewall created in the next step.
  • scopes: Defines the Oauth scopes required by the nodes.
  • num-nodes: The number of nodes to be created in each of the cluster’s zones. Default: 4. Depending on the needs of your game, this parameter should be adjusted.
  • no-enable-autoupgrade: Disable automatic upgrades for nodes to reduce the likelihood of in-use games being disrupted.
  • machine-type: The type of machine to use for nodes. Default: n1-standard-4. Depending on the needs of your game, you may wish to have smaller or larger machines.

Optional: Create a dedicated node pool for the Agones controllers. If you choose to skip this step, the Agones controllers will share the default node pool with your game servers which is fine for kicking the tires but is not recommended for a production deployment.

gcloud container node-pools create agones-system \
  --cluster=[CLUSTER_NAME] \
  --no-enable-autoupgrade \
  --node-taints agones.dev/agones-system=true:NoExecute \
  --node-labels agones.dev/agones-system=true \
  --num-nodes=1

Optional: Create a node pool for Metrics if you want to monitor the Agones system using Prometheus with Grafana or Stackdriver.

gcloud container node-pools create agones-metrics \
  --cluster=[CLUSTER_NAME] \
  --no-enable-autoupgrade \
  --node-taints agones.dev/agones-metrics=true:NoExecute \
  --node-labels agones.dev/agones-metrics=true \
  --num-nodes=1

Flag explanations:

  • cluster: The name of the cluster in which the node pool is created.
  • no-enable-autoupgrade: Disable automatic upgrades for nodes to reduce the likelihood of in-use games being disrupted.
  • node-taints: The Kubernetes taints to automatically apply to nodes in this node pool.
  • node-labels: The Kubernetes labels to automatically apply to nodes in this node pool.
  • num-nodes: The Agones system controllers only require a single node of capacity to run. For faster recovery time in the event of a node failure, you can increase the size to 2.

Finally, let’s tell gcloud that we are speaking with this cluster, and get auth credentials for kubectl to use.

gcloud config set container/cluster [CLUSTER_NAME]
gcloud container clusters get-credentials [CLUSTER_NAME]

Creating the firewall

We need a firewall to allow UDP traffic to nodes tagged as game-server via ports 7000-8000.

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

Next Steps