# Google Cloud In this tutorial, we'll create a Kubernetes v1.9.4 cluster on Google Compute Engine (not GKE). We'll declare a Kubernetes cluster in Terraform using the Typhoon Terraform module. On apply, a network, firewall rules, managed instance groups of Kubernetes controllers and workers, network load balancers for controllers and workers, and health checks will be created. Controllers and workers are provisioned to run a `kubelet`. A one-time [bootkube](https://github.com/kubernetes-incubator/bootkube) bootstrap schedules an `apiserver`, `scheduler`, `controller-manager`, and `kube-dns` on controllers and runs `kube-proxy` and `calico` or `flannel` on each 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 v0.11.x and [terraform-provider-ct](https://github.com/coreos/terraform-provider-ct) installed locally ## Terraform Setup Install [Terraform](https://www.terraform.io/downloads.html) v0.11.x on your system. ```sh $ terraform version Terraform v0.11.1 ``` Add the [terraform-provider-ct](https://github.com/coreos/terraform-provider-ct) plugin binary for your system. ```sh wget https://github.com/coreos/terraform-provider-ct/releases/download/v0.2.1/terraform-provider-ct-v0.2.1-linux-amd64.tar.gz tar xzf terraform-provider-ct-v0.2.1-linux-amd64.tar.gz sudo mv terraform-provider-ct-v0.2.1-linux-amd64/terraform-provider-ct /usr/local/bin/ ``` Add the plugin to your `~/.terraformrc`. ``` providers { ct = "/usr/local/bin/terraform-provider-ct" } ``` Read [concepts](concepts.md) 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 service account key credentials. Choose the "Compute Engine default service account" 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" { version = "1.2" alias = "default" credentials = "${file("~/.config/google-cloud/terraform.json")}" project = "project-id" region = "us-central1" } provider "local" { version = "~> 1.0" alias = "default" } provider "null" { version = "~> 1.0" alias = "default" } provider "template" { version = "~> 1.0" alias = "default" } provider "tls" { version = "~> 1.0" alias = "default" } ``` Additional configuration options are described in the `google` provider [docs](https://www.terraform.io/docs/providers/google/index.html). !!! tip A project may contain multiple clusters if you wish. Regions are listed in [docs](https://cloud.google.com/compute/docs/regions-zones/regions-zones) or with `gcloud compute regions list`. ## Cluster Define a Kubernetes cluster using the module `google-cloud/container-linux/kubernetes`. ```tf module "google-cloud-yavin" { source = "git::https://github.com/poseidon/typhoon//google-cloud/container-linux/kubernetes?ref=v1.9.4" providers = { google = "google.default" local = "local.default" null = "null.default" template = "template.default" tls = "tls.default" } # Google Cloud region = "us-central1" dns_zone = "example.com" dns_zone_name = "example-zone" os_image = "coreos-stable" cluster_name = "yavin" controller_count = 1 worker_count = 2 ssh_authorized_key = "ssh-rsa AAAAB3Nz..." # output assets dir asset_dir = "/home/user/.secrets/clusters/yavin" } ``` Reference the [variables docs](#variables) or the [variables.tf](https://github.com/poseidon/typhoon/blob/master/google-cloud/container-linux/kubernetes/variables.tf) source. ## ssh-agent Initial bootstrapping requires `bootkube.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 ``` !!! warning `terraform apply` will hang connecting to a controller if `ssh-agent` does not contain the SSH key. ## Apply Initialize the config directory if this is the first use with Terraform. ```sh terraform init ``` Get or update Terraform modules. ```sh $ terraform get # downloads missing modules $ terraform get --update # updates all modules Get: git::https://github.com/poseidon/typhoon (update) Get: git::https://github.com/poseidon/bootkube-terraform.git?ref=v0.11.0 (update) ``` 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.google-cloud-yavin.null_resource.bootkube-start: Still creating... (10s elapsed) ... module.google-cloud-yavin.null_resource.bootkube-start: Still creating... (5m30s elapsed) module.google-cloud-yavin.null_resource.bootkube-start: Still creating... (5m40s elapsed) module.google-cloud-yavin.null_resource.bootkube-start: Creation complete (ID: 5768638456220583358) Apply complete! Resources: 64 added, 0 changed, 0 destroyed. ``` In 4-8 minutes, the Kubernetes cluster will be ready. ## Verify [Install kubectl](https://coreos.com/kubernetes/docs/latest/configure-kubectl.html) on your system. Use the generated `kubeconfig` credentials to access the Kubernetes cluster and list nodes. ``` $ export KUBECONFIG=/home/user/.secrets/clusters/yavin/auth/kubeconfig $ kubectl get nodes NAME STATUS AGE VERSION yavin-controller-0.c.example-com.internal Ready 6m v1.9.4 yavin-worker-jrbf.c.example-com.internal Ready 5m v1.9.4 yavin-worker-mzdm.c.example-com.internal Ready 5m v1.9.4 ``` 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 kube-apiserver-zppls 1/1 Running 0 6m kube-system kube-controller-manager-3271970485-gh9kt 1/1 Running 0 6m kube-system kube-controller-manager-3271970485-h90v8 1/1 Running 1 6m kube-system kube-dns-1187388186-zj5dl 3/3 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-3895335239-5x87r 1/1 Running 0 6m kube-system kube-scheduler-3895335239-bzrrt 1/1 Running 1 6m kube-system pod-checkpointer-l6lrt 1/1 Running 0 6m ``` ## Going Further Learn about [maintenance](topics/maintenance.md) and [addons](addons/overview.md). !!! note On Container Linux clusters, install the `CLUO` addon to coordinate reboots and drains when nodes auto-update. Otherwise, updates may not be applied until the next reboot. ## Variables ### 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 ~/.ssh_authorized_keys | "ssh-rsa AAAAB3NZ..." | | asset_dir | Path to a directory where generated assets should be placed (contains secrets) | "/home/user/.secrets/clusters/yavin" | 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 network load balancer backed by controller instances. This FQDN is used by workers and `kubectl` to access the apiserver. In this example, the cluster's apiserver would be accessible at `yavin.google-cloud.example.com`. You'll need a registered domain name or subdomain registered in a Google Cloud DNS zone. 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 carve out 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 | 1 | | worker_count | Number of workers | 1 | 3 | | machine_type | Machine type for compute instances | "n1-standard-1" | See below | | os_image | OS image for compute instances | "coreos-stable" | "coreos-stable-1632-3-0-v20180215" | | worker_preemptible | If enabled, Compute Engine will terminate workers randomly within 24 hours | false | true | | networking | Choice of networking provider | "calico" | "calico" or "flannel" | | pod_cidr | CIDR range to assign to Kubernetes pods | "10.2.0.0/16" | "10.22.0.0/16" | | service_cidr | CIDR range to assign to Kubernetes services | "10.3.0.0/16" | "10.3.0.0/24" | | cluster_domain_suffix | FQDN suffix for Kubernetes services answered by kube-dns. | "cluster.local" | "k8s.example.com" | | controller_clc_snippets | Controller Container Linux Config snippets | [] | | | worker_clc_snippets | Worker Container Linux Config snippets | [] | | Check the list of valid [machine types](https://cloud.google.com/compute/docs/machine-types). !!! warning Set controller_count to 1. A bug in Google Cloud network load balancer health checking prevents multiple controllers from bootstrapping. There are workarounds, but they all involve tradeoffs we're uncomfortable recommending. See [#54](https://github.com/poseidon/typhoon/issues/54). #### Preemption Add `worker_preemeptible = "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.`