# Google Cloud In this tutorial, we'll create a Kubernetes v1.23.4 cluster on Google Compute Engine with Flatcar Linux. We'll declare a Kubernetes cluster using the Typhoon Terraform module. Then apply the changes to create a network, firewall rules, health checks, controller instances, worker managed instance group, load balancers, and TLS assets. Controller hosts are provisioned to run an `etcd-member` peer and a `kubelet` service. Worker hosts run a `kubelet` service. Controller nodes run `kube-apiserver`, `kube-scheduler`, `kube-controller-manager`, and `coredns`, while `kube-proxy` and `calico` (or `flannel`) run on every node. A generated `kubeconfig` provides `kubectl` access to the cluster. ## Requirements * Google Cloud Account and Service Account * Google Cloud DNS Zone (registered Domain Name or delegated subdomain) * Terraform v0.13.0+ ## Terraform Setup Install [Terraform](https://www.terraform.io/downloads.html) v0.13.0+ on your system. ```sh $ terraform version Terraform v1.0.0 ``` Read [concepts](/architecture/concepts/) to learn about Terraform, modules, and organizing resources. Change to your infrastructure repository (e.g. `infra`). ``` cd infra/clusters ``` ## Provider Login to your Google Console [API Manager](https://console.cloud.google.com/apis/dashboard) and select a project, or [signup](https://cloud.google.com/free/) if you don't have an account. Select "Credentials" and create a service account key. Choose the "Compute Engine Admin" and "DNS Administrator" roles and save the JSON private key to a file that can be referenced in configs. ```sh mv ~/Downloads/project-id-43048204.json ~/.config/google-cloud/terraform.json ``` Configure the Google Cloud provider to use your service account key, project-id, and region in a `providers.tf` file. ```tf provider "google" { project = "project-id" region = "us-central1" credentials = file("~/.config/google-cloud/terraform.json") } provider "ct" {} terraform { required_providers { ct = { source = "poseidon/ct" version = "0.9.1" } google = { source = "hashicorp/google" version = "4.7.0" } } } ``` Additional configuration options are described in the `google` provider [docs](https://www.terraform.io/docs/providers/google/index.html). !!! tip Regions are listed in [docs](https://cloud.google.com/compute/docs/regions-zones/regions-zones) or with `gcloud compute regions list`. A project may contain multiple clusters across different regions. ## Cluster Define a Kubernetes cluster using the module `google-cloud/flatcar-linux/kubernetes`. ```tf module "yavin" { source = "git::https://github.com/poseidon/typhoon//google-cloud/flatcar-linux/kubernetes?ref=v1.23.4" # Google Cloud cluster_name = "yavin" region = "us-central1" dns_zone = "example.com" dns_zone_name = "example-zone" # configuration ssh_authorized_key = "ssh-rsa AAAAB3Nz..." # optional worker_count = 2 } ``` Reference the [variables docs](#variables) or the [variables.tf](https://github.com/poseidon/typhoon/blob/master/google-cloud/flatcar-linux/kubernetes/variables.tf) source. ## ssh-agent Initial bootstrapping requires `bootstrap.service` be started on one controller node. Terraform uses `ssh-agent` to automate this step. Add your SSH private key to `ssh-agent`. ```sh ssh-add ~/.ssh/id_rsa ssh-add -L ``` ## Apply Initialize the config directory if this is the first use with Terraform. ```sh terraform init ``` Plan the resources to be created. ```sh $ terraform plan Plan: 64 to add, 0 to change, 0 to destroy. ``` Apply the changes to create the cluster. ```sh $ terraform apply module.yavin.null_resource.bootstrap: Still creating... (10s elapsed) ... module.yavin.null_resource.bootstrap: Still creating... (5m30s elapsed) module.yavin.null_resource.bootstrap: Still creating... (5m40s elapsed) module.yavin.null_resource.bootstrap: Creation complete (ID: 5768638456220583358) Apply complete! Resources: 62 added, 0 changed, 0 destroyed. ``` In 4-8 minutes, the Kubernetes cluster will be ready. ## Verify [Install kubectl](https://kubernetes.io/docs/tasks/tools/install-kubectl/) on your system. Obtain the generated cluster `kubeconfig` from module outputs (e.g. write to a local file). ``` resource "local_file" "kubeconfig-yavin" { content = module.yavin.kubeconfig-admin filename = "/home/user/.kube/configs/yavin-config" } ``` List nodes in the cluster. ``` $ export KUBECONFIG=/home/user/.kube/configs/yavin-config $ kubectl get nodes NAME ROLES STATUS AGE VERSION yavin-controller-0.c.example-com.internal Ready 6m v1.23.4 yavin-worker-jrbf.c.example-com.internal Ready 5m v1.23.4 yavin-worker-mzdm.c.example-com.internal Ready 5m v1.23.4 ``` List the pods. ``` $ kubectl get pods --all-namespaces NAMESPACE NAME READY STATUS RESTARTS AGE kube-system calico-node-1cs8z 2/2 Running 0 6m kube-system calico-node-d1l5b 2/2 Running 0 6m kube-system calico-node-sp9ps 2/2 Running 0 6m kube-system coredns-1187388186-dkh3o 1/1 Running 0 6m kube-system coredns-1187388186-zj5dl 1/1 Running 0 6m kube-system kube-apiserver-controller-0 1/1 Running 0 6m kube-system kube-controller-manager-controller-0 1/1 Running 0 6m kube-system kube-proxy-117v6 1/1 Running 0 6m kube-system kube-proxy-9886n 1/1 Running 0 6m kube-system kube-proxy-njn47 1/1 Running 0 6m kube-system kube-scheduler-controller-0 1/1 Running 0 6m ``` ## Going Further Learn about [maintenance](/topics/maintenance/) and [addons](/addons/overview/). ## Variables Check the [variables.tf](https://github.com/poseidon/typhoon/blob/master/google-cloud/flatcar-linux/kubernetes/variables.tf) source. ### Required | Name | Description | Example | |:-----|:------------|:--------| | cluster_name | Unique cluster name (prepended to dns_zone) | "yavin" | | region | Google Cloud region | "us-central1" | | dns_zone | Google Cloud DNS zone | "google-cloud.example.com" | | dns_zone_name | Google Cloud DNS zone name | "example-zone" | | ssh_authorized_key | SSH public key for user 'core' | "ssh-rsa AAAAB3NZ..." | Check the list of valid [regions](https://cloud.google.com/compute/docs/regions-zones/regions-zones) and list Container Linux [images](https://cloud.google.com/compute/docs/images) with `gcloud compute images list | grep coreos`. #### DNS Zone Clusters create a DNS A record `${cluster_name}.${dns_zone}` to resolve a TCP proxy load balancer backed by controller instances. This FQDN is used by workers and `kubectl` to access the apiserver(s). In this example, the cluster's apiserver would be accessible at `yavin.google-cloud.example.com`. You'll need a registered domain name or delegated subdomain on Google Cloud DNS. You can set this up once and create many clusters with unique names. ```tf resource "google_dns_managed_zone" "zone-for-clusters" { dns_name = "google-cloud.example.com." name = "example-zone" description = "Production DNS zone" } ``` !!! tip "" If you have an existing domain name with a zone file elsewhere, just delegate a subdomain that can be managed on Google Cloud (e.g. google-cloud.mydomain.com) and [update nameservers](https://cloud.google.com/dns/update-name-servers). ### Optional | Name | Description | Default | Example | |:-----|:------------|:--------|:--------| | controller_count | Number of controllers (i.e. masters) | 1 | 3 | | worker_count | Number of workers | 1 | 3 | | controller_type | Machine type for controllers | "n1-standard-1" | See below | | worker_type | Machine type for workers | "n1-standard-1" | See below | | os_image | Flatcar Linux image for compute instances | "flatcar-stable" | flatcar-stable, flatcar-beta, flatcar-alpha | | disk_size | Size of the disk in GB | 30 | 100 | | worker_preemptible | If enabled, Compute Engine will terminate workers randomly within 24 hours | false | true | | controller_snippets | Controller Container Linux Config snippets | [] | [example](/advanced/customization/) | | worker_snippets | Worker Container Linux Config snippets | [] | [example](/advanced/customization/) | | networking | Choice of networking provider | "cilium" | "calico" or "cilium" or "flannel" | | pod_cidr | CIDR IPv4 range to assign to Kubernetes pods | "10.2.0.0/16" | "10.22.0.0/16" | | service_cidr | CIDR IPv4 range to assign to Kubernetes services | "10.3.0.0/16" | "10.3.0.0/24" | | worker_node_labels | List of initial worker node labels | [] | ["worker-pool=default"] | Check the list of valid [machine types](https://cloud.google.com/compute/docs/machine-types). #### Preemption Add `worker_preemptible = "true"` to allow worker nodes to be [preempted](https://cloud.google.com/compute/docs/instances/preemptible) at random, but pay [significantly](https://cloud.google.com/compute/pricing) less. Clusters tolerate stopping instances fairly well (reschedules pods, but cannot drain) and preemption provides a nice reward for running fault-tolerant cluster systems.`