How to Create Terraform code for GKE cluster - kubernetes

We can create/see the gcloud command from GKE cluster creation UI , is there a way to convert the command into terraform code for GKE cluster. thanks

You can create GKE cluster by using terraform. There is a official link, by following you need to write the .tf file and apply.
resource "google_container_cluster" "primary" {
name = "my-gke-cluster"
location = "us-central1"
initial_node_count = 1
master_auth {
username = ""
password = ""
client_certificate_config {
issue_client_certificate = false
}
}
}
This is an useful tutorial.

Related

GCP: using image from one account's Artifact Registry on other account

Hello and wish you a great time!
I've got following terraform service account deffinition:
resource "google_service_account" "gke_service_account" {
project = var.context
account_id = var.gke_account_name
display_name = var.gke_account_description
}
That I use in GCP kubernetes node pool:
resource "google_container_node_pool" "gke_node_pool" {
name = "${var.context}-gke-node"
location = var.region
project = var.context
cluster = google_container_cluster.gke_cluster.name
management {
auto_repair = "true"
auto_upgrade = "true"
}
autoscaling {
min_node_count = var.gke_min_node_count
max_node_count = var.gke_max_node_count
}
initial_node_count = var.gke_min_node_count
node_config {
machine_type = var.gke_machine_type
service_account = google_service_account.gke_service_account.email
metadata = {
disable-legacy-endpoints = "true"
}
# Needed for correctly functioning cluster, see
# https://www.terraform.io/docs/providers/google/r/container_cluster.html#oauth_scopes
oauth_scopes = [
"https://www.googleapis.com/auth/logging.write",
"https://www.googleapis.com/auth/monitoring",
"https://www.googleapis.com/auth/devstorage.read_only",
"https://www.googleapis.com/auth/servicecontrol",
"https://www.googleapis.com/auth/cloud-platform"
]
}
}
However the current solution requires the prod and dev envs to be on various GCP accounts but use the same image from prod artifact registry.
As for now I have JSON key file for service account in prod having access to it's registry. Maybe there's a pretty way to use the json file as a second service account for kubernetes or update current k8s service account with json file to have additional permissions to the remote registry?
I've seen the solutions like put it to a secret or user cross-account-service-account.
But it's not the way I want to resolve it since we have some internal restrictions.
Hope someone faced similar task and has a solution to share - it'll save me real time.
Thanks in advance!

Automated .kube/config file created with Terraform GKE module doesn't work

We are using the below terraform module to create the GKE cluster and the local config file. But the kubectl command doesn't work. The terminal just keeps on waiting. Then we have to manually run the command gcloud container clusters get-credentials to fetch and set up the local config credentials post the cluster creation, and then the kubectl command works. It doesn't feel elegant to execute the gcloud command after the terraform setup. Therefore please help to correct what's wrong.
terraform {
required_providers {
google = {
source = "hashicorp/google"
version = ">= 3.42.0"
}
google-beta = {
source = "hashicorp/google-beta"
version = ">= 3.0.0"
}
}
}
provider "google" {
credentials = var.gcp_creds
project = var.project_id
region = var.region
zone = var.zone
}
provider "google-beta" {
credentials = var.gcp_creds
project = var.project_id
region = var.region
zone = var.zone
}
module "gke" {
source = "terraform-google-modules/kubernetes-engine/google//modules/beta-private-cluster"
project_id = var.project_id
name = "cluster"
regional = true
region = var.region
zones = ["${var.region}-a", "${var.region}-b", "${var.region}-c"]
network = module.vpc.network_name
subnetwork = module.vpc.subnets_names[0]
ip_range_pods = "gke-pod-ip-range"
ip_range_services = "gke-service-ip-range"
horizontal_pod_autoscaling = true
enable_private_nodes = true
master_ipv4_cidr_block = "${var.control_plane_cidr}"
node_pools = [
{
name = "node-pool"
machine_type = "${var.machine_type}"
node_locations = "${var.region}-a,${var.region}-b,${var.region}-c"
min_count = "${var.node_pools_min_count}"
max_count = "${var.node_pools_max_count}"
disk_size_gb = "${var.node_pools_disk_size_gb}"
auto_repair = true
auto_upgrade = true
},
]
}
# Configure the authentication and authorisation of the cluster
module "gke_auth" {
source = "terraform-google-modules/kubernetes-engine/google//modules/auth"
depends_on = [module.gke]
project_id = var.project_id
location = module.gke.location
cluster_name = module.gke.name
}
# Define a local file that will store the necessary info such as certificate, user and endpoint to access the cluster
resource "local_file" "kubeconfig" {
content = module.gke_auth.kubeconfig_raw
filename = "~/.kube/config"
}
UPDATE:
We found that the automated .kube/config file was created with the wrong public IP of the API Server whereas the one created with the gcloud command contains the correct IP of the API Server. Any guesses why terraform one is fetching the wrong public IP?

How can I configure an AWS EKS autoscaler with Terraform?

I'm using the AWS EKS provider (github.com/terraform-aws-modules/terraform-aws-eks ). I'm following along the tutorial with https://learn.hashicorp.com/terraform/aws/eks-intro
However this does not seem to have autoscaling enabled... It seems it's missing the cluster-autoscaler pod / daemon?
Is Terraform able to provision this functionality? Or do I need to set this up following a guide like: https://eksworkshop.com/scaling/deploy_ca/
You can deploy Kubernetes resources using Terraform. There is both a Kubernetes provider and a Helm provider.
data "aws_eks_cluster_auth" "authentication" {
name = "${var.cluster_id}"
}
provider "kubernetes" {
# Use the token generated by AWS iam authenticator to connect as the provider does not support exec auth
# see: https://github.com/terraform-providers/terraform-provider-kubernetes/issues/161
host = "${var.cluster_endpoint}"
cluster_ca_certificate = "${base64decode(var.cluster_certificate_authority_data)}"
token = "${data.aws_eks_cluster_auth.authentication.token}"
load_config_file = false
}
provider "helm" {
install_tiller = "true"
tiller_image = "gcr.io/kubernetes-helm/tiller:v2.12.3"
}
resource "helm_release" "cluster_autoscaler" {
name = "cluster-autoscaler"
repository = "stable"
chart = "cluster-autoscaler"
namespace = "kube-system"
version = "0.12.2"
set {
name = "autoDiscovery.enabled"
value = "true"
}
set {
name = "autoDiscovery.clusterName"
value = "${var.cluster_name}"
}
set {
name = "cloudProvider"
value = "aws"
}
set {
name = "awsRegion"
value = "${data.aws_region.current_region.name}"
}
set {
name = "rbac.create"
value = "true"
}
set {
name = "sslCertPath"
value = "/etc/ssl/certs/ca-bundle.crt"
}
}
This answer below is still not complete... But at least it gets me partially further...
1.
kubectl create clusterrolebinding add-on-cluster-admin --clusterrole=cluster-admin --serviceaccount=kube-system:default
helm install stable/cluster-autoscaler --name my-release --set "autoscalingGroups[0].name=demo,autoscalingGroups[0].maxSize=10,autoscalingGroups[0].minSize=1" --set rbac.create=true
And then manually fix the certificate path:
kubectl edit deployments my-release-aws-cluster-autoscaler
replace the following:
path: /etc/ssl/certs/ca-bundle.crt
With
path: /etc/ssl/certs/ca-certificates.crt
2.
In the AWS console, give AdministratorAccess policy to the terraform-eks-demo-node role.
3.
Update the nodes parameter with (kubectl edit deployments my-release-aws-cluster-autoscaler)
- --nodes=1:10:terraform-eks-demo20190922124246790200000007

Terraform - staggered provider population

I have been looking at implementing Kubernetes with Terraform over the past week and I seem to have a lifecycle issue.
While I can make a Kubernetes resource depend on a cluster being spun up, the KUBECONFIG file isn't updated in the middle of the terraform apply.
The kubernete
resource "kubernetes_service" "example" {
...
depends_on = ["digitalocean_kubernetes_cluster.example"]
}
resource "digitalocean_kubernetes_cluster" "example" {
name = "example"
region = "${var.region}"
version = "1.12.1-do.2"
node_pool {
name = "woker-pool"
size = "s-1vcpu-2gb"
node_count = 1
}
provisioner "local-exec" {
command = "sh ./get-kubeconfig.sh" // gets KUBECONFIG file from digitalocean API.
environment = {
digitalocean_kubernetes_cluster_id = "${digitalocean_kubernetes_cluster.k8s.id}"
digitalocean_kubernetes_cluster_name = "${digitalocean_kubernetes_cluster.k8s.name}"
digitalocean_api_token = "${var.digitalocean_token}"
}
}
While I can pull the CONFIG file down using the API, terraform won't use this file, because the terraform plan is already in motion
I've seen some examples using ternary operators (resource ? 1 : 0) but I haven't found a workaround for non count created clusters besides -target
Ideally, I'd like to create this with one terraform repo.
It turns out that the digitalocean_kubernetes_cluster resource has an attribute which can be passed to the provider "kubernetes" {} like so:
resource "digitalocean_kubernetes_cluster" "k8s" {
name = "k8s"
region = "${var.region}"
version = "1.12.1-do.2"
node_pool {
name = "woker-pool"
size = "s-1vcpu-2gb"
node_count = 1
}
}
provider "kubernetes" {
host = "${digitalocean_kubernetes_cluster.k8s.endpoint}"
client_certificate = "${base64decode(digitalocean_kubernetes_cluster.k8s.kube_config.0.client_certificate)}"
client_key = "${base64decode(digitalocean_kubernetes_cluster.k8s.kube_config.0.client_key)}"
cluster_ca_certificate = "${base64decode(digitalocean_kubernetes_cluster.k8s.kube_config.0.cluster_ca_certificate)}"
}
It results in one provider being dependant on the other, and acts accordingly.

Terraform: How to create a Kubernetes cluster on Google Cloud (GKE) with namespaces?

I'm after an example that would do the following:
Create a Kubernetes cluster on GKE via Terraform's google_container_cluster
... and continue creating namespaces in it, I suppose via kubernetes_namespace
The thing I'm not sure about is how to connect the newly created cluster and the namespace definition. For example, when adding google_container_node_pool, I can do something like cluster = "${google_container_cluster.hosting.name}" but I don't see anything similar for kubernetes_namespace.
In theory it is possible to reference resources from the GCP provider in K8S (or any other) provider in the same way you'd reference resources or data sources within the context of a single provider.
provider "google" {
region = "us-west1"
}
data "google_compute_zones" "available" {}
resource "google_container_cluster" "primary" {
name = "the-only-marcellus-wallace"
zone = "${data.google_compute_zones.available.names[0]}"
initial_node_count = 3
additional_zones = [
"${data.google_compute_zones.available.names[1]}"
]
master_auth {
username = "mr.yoda"
password = "adoy.rm"
}
node_config {
oauth_scopes = [
"https://www.googleapis.com/auth/compute",
"https://www.googleapis.com/auth/devstorage.read_only",
"https://www.googleapis.com/auth/logging.write",
"https://www.googleapis.com/auth/monitoring"
]
}
}
provider "kubernetes" {
host = "https://${google_container_cluster.primary.endpoint}"
username = "${google_container_cluster.primary.master_auth.0.username}"
password = "${google_container_cluster.primary.master_auth.0.password}"
client_certificate = "${base64decode(google_container_cluster.primary.master_auth.0.client_certificate)}"
client_key = "${base64decode(google_container_cluster.primary.master_auth.0.client_key)}"
cluster_ca_certificate = "${base64decode(google_container_cluster.primary.master_auth.0.cluster_ca_certificate)}"
}
resource "kubernetes_namespace" "n" {
metadata {
name = "blablah"
}
}
However in practice it may not work as expected due to a known core bug breaking cross-provider dependencies, see https://github.com/hashicorp/terraform/issues/12393 and https://github.com/hashicorp/terraform/issues/4149 respectively.
The alternative solution would be:
Use 2-staged apply and target the GKE cluster first, then anything else that depends on it, i.e. terraform apply -target=google_container_cluster.primary and then terraform apply
Separate out GKE cluster config from K8S configs, give them completely isolated workflow and connect those via remote state.
/terraform-gke/main.tf
terraform {
backend "gcs" {
bucket = "tf-state-prod"
prefix = "terraform/state"
}
}
provider "google" {
region = "us-west1"
}
data "google_compute_zones" "available" {}
resource "google_container_cluster" "primary" {
name = "the-only-marcellus-wallace"
zone = "${data.google_compute_zones.available.names[0]}"
initial_node_count = 3
additional_zones = [
"${data.google_compute_zones.available.names[1]}"
]
master_auth {
username = "mr.yoda"
password = "adoy.rm"
}
node_config {
oauth_scopes = [
"https://www.googleapis.com/auth/compute",
"https://www.googleapis.com/auth/devstorage.read_only",
"https://www.googleapis.com/auth/logging.write",
"https://www.googleapis.com/auth/monitoring"
]
}
}
output "gke_host" {
value = "https://${google_container_cluster.primary.endpoint}"
}
output "gke_username" {
value = "${google_container_cluster.primary.master_auth.0.username}"
}
output "gke_password" {
value = "${google_container_cluster.primary.master_auth.0.password}"
}
output "gke_client_certificate" {
value = "${base64decode(google_container_cluster.primary.master_auth.0.client_certificate)}"
}
output "gke_client_key" {
value = "${base64decode(google_container_cluster.primary.master_auth.0.client_key)}"
}
output "gke_cluster_ca_certificate" {
value = "${base64decode(google_container_cluster.primary.master_auth.0.cluster_ca_certificate)}"
}
Here we're exposing all the necessary configuration via outputs and use backend to store the state, along with these outputs in a remote location, GCS in this case. This enables us to reference it in the config below.
/terraform-k8s/main.tf
data "terraform_remote_state" "foo" {
backend = "gcs"
config {
bucket = "tf-state-prod"
prefix = "terraform/state"
}
}
provider "kubernetes" {
host = "https://${data.terraform_remote_state.foo.gke_host}"
username = "${data.terraform_remote_state.foo.gke_username}"
password = "${data.terraform_remote_state.foo.gke_password}"
client_certificate = "${base64decode(data.terraform_remote_state.foo.gke_client_certificate)}"
client_key = "${base64decode(data.terraform_remote_state.foo.gke_client_key)}"
cluster_ca_certificate = "${base64decode(data.terraform_remote_state.foo.gke_cluster_ca_certificate)}"
}
resource "kubernetes_namespace" "n" {
metadata {
name = "blablah"
}
}
What may or may not be obvious here is that cluster has to be created/updated before creating/updating any K8S resources (if such update relies on updates of the cluster).
Taking the 2nd approach is generally advisable either way (even when/if the bug was not a factor and cross-provider references worked) as it reduces the blast radius and defines much clearer responsibility. It's (IMO) common for such deployment to have 1 person/team responsible for managing the cluster and a different one for managing K8S resources.
There may certainly be overlaps though - e.g. ops wanting to deploy logging & monitoring infrastructure on top of a fresh GKE cluster, so cross provider dependencies aim to satisfy such use cases. For that reason I'd recommend subscribing to the GH issues mentioned above.