Add support for worker pools on google-cloud

* Set defaults for internal worker module's count,
machine_type, and os_image
* Allow "pools" of homogeneous workers to be created
using the google-cloud/kubernetes/workers module
This commit is contained in:
Dalton Hubble 2018-02-26 14:06:18 -08:00
parent 06d40c5b44
commit 160ae34e71
8 changed files with 100 additions and 13 deletions

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@ -24,6 +24,7 @@ Notable changes between versions.
#### Google Cloud
* Add support for "worker pools" - groups of homogeneous workers joined to an existing cluster ([#148](https://github.com/poseidon/typhoon/pull/148))
* Add kubelet `--volume-plugin-dir` flag to allow flexvolume plugins ([#142](https://github.com/poseidon/typhoon/pull/142))
* Add `kubeconfig` variable to `controllers` and `workers` submodules ([#147](https://github.com/poseidon/typhoon/pull/147))
* Remove `kubeconfig_*` variables from `controllers` and `workers` submodules ([#147](https://github.com/poseidon/typhoon/pull/147))

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@ -0,0 +1,6 @@
# Advanced
Typhoon clusters offer several advanced features for skilled users.
* [Customization](customization.md)
* [Worker Pools](worker-pools.md)

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@ -0,0 +1,71 @@
# Worker Pools
Typhoon can create "worker pools", groups of homogeneous workers that are part of an existing cluster. For example, you may wish to augment a Kubernetes cluster with groups of workers with a different machine type, larger disks, or preemptibility.
## Google Cloud
Create a cluster following the Google Cloud [tutorial](../google-cloud.md#cluster). Then define a worker pool using the internal `workers` Terraform module.
```tf
module "yavin-worker-pool" {
source = "git::https://github.com/poseidon/typhoon//google-cloud/container-linux/kubernetes/workers?ref=v1.9.4"
# Google Cloud
network = "${module.google-cloud-yavin.network_name}"
region = "us-central1"
count = 2
machine_type = "n1-standard-16"
preemptible = true
cluster_name = "yavin-16x"
ssh_authorized_key = "${var.ssh_authorized_key}"
kubeconfig = "${module.google-cloud-yavin.kubeconfig}"
}
```
Apply the change.
```
terraform apply
```
Verify a managed instance group of workers joins the cluster within a few minutes.
```
$ kubectl get nodes
NAME STATUS AGE VERSION
yavin-controller-0.c.example-com.internal Ready 6m v1.9.3
yavin-worker-jrbf.c.example-com.internal Ready 5m v1.9.3
yavin-worker-mzdm.c.example-com.internal Ready 5m v1.9.3
yavin-16x-worker-jrbf.c.example-com.internal Ready 3m v1.9.3
yavin-16x-worker-mzdm.c.example-com.internal Ready 3m v1.9.3
```
### Variables
The Google Cloud internal `workers` module supports a number of [variables](https://github.com/poseidon/typhoon/blob/master/google-cloud/container-linux/kubernetes/workers/variables.tf).
#### Required
| Name | Description | Example |
|:-----|:------------|:--------|
| cluster_name | Unique name | "yavin-worker-pool" |
| region | Must match region of cluster | "us-central1" |
| network | Must match network name output by cluster | "${module.cluster.network_name}" |
| ssh_authorized_key | SSH public key for ~/.ssh_authorized_keys | "ssh-rsa AAAAB3NZ..." |
#### Optional
| Name | Description | Default | Example |
|:-----|:------------|:--------|:--------|
| 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-alpha" |
| disk_size | Size of the disk in GB | 40 | 100 |
| preemptible | If enabled, Compute Engine will terminate instances randomly within 24 hours | false | true |
| service_cidr | Must match service_cidr of cluster | "10.3.0.0/16" | "10.3.0.0/24" |
| cluster_domain_suffix | Must match domain suffix of cluster | "cluster.local" | "k8s.example.com" |
Check the list of valid [machine types](https://cloud.google.com/compute/docs/machine-types).

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@ -257,7 +257,7 @@ resource "google_dns_managed_zone" "zone-for-clusters" {
| machine_type | Machine type for compute instances | "n1-standard-1" | See below |
| controller_count | Number of controllers (i.e. masters) | 1 | 1 |
| worker_count | Number of workers | 1 | 3 |
| worker_preemptible | If enabled, Compute Engine will terminate controllers randomly within 24 hours | false | true |
| 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" |

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@ -1,7 +1,6 @@
module "controllers" {
source = "controllers"
cluster_name = "${var.cluster_name}"
ssh_authorized_key = "${var.ssh_authorized_key}"
# GCE
network = "${google_compute_network.network.name}"
@ -14,15 +13,15 @@ module "controllers" {
# configuration
networking = "${var.networking}"
kubeconfig = "${module.bootkube.kubeconfig}"
ssh_authorized_key = "${var.ssh_authorized_key}"
service_cidr = "${var.service_cidr}"
cluster_domain_suffix = "${var.cluster_domain_suffix}"
kubeconfig = "${module.bootkube.kubeconfig}"
}
module "workers" {
source = "workers"
cluster_name = "${var.cluster_name}"
ssh_authorized_key = "${var.ssh_authorized_key}"
# GCE
network = "${google_compute_network.network.name}"
@ -33,7 +32,8 @@ module "workers" {
preemptible = "${var.worker_preemptible}"
# configuration
kubeconfig = "${module.bootkube.kubeconfig}"
ssh_authorized_key = "${var.ssh_authorized_key}"
service_cidr = "${var.service_cidr}"
cluster_domain_suffix = "${var.cluster_domain_suffix}"
kubeconfig = "${module.bootkube.kubeconfig}"
}

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@ -13,3 +13,7 @@ output "network_name" {
output "network_self_link" {
value = "${google_compute_network.network.self_link}"
}
output "kubeconfig" {
value = "${module.bootkube.kubeconfig}"
}

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@ -17,6 +17,7 @@ variable "network" {
variable "count" {
type = "string"
default = "1"
description = "Number of worker compute instances the instance group should manage"
}
@ -27,11 +28,13 @@ variable "region" {
variable "machine_type" {
type = "string"
default = "n1-standard-1"
description = "Machine type for compute instances (e.g. gcloud compute machine-types list)"
}
variable "os_image" {
type = "string"
default = "coreos-stable"
description = "OS image from which to initialize the disk (e.g. gcloud compute images list)"
}

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@ -58,4 +58,6 @@ pages:
- 'Performance': 'topics/performance.md'
- 'FAQ': 'faq.md'
- 'Advanced':
- 'Overview': 'advanced/overview.md'
- 'Customization': 'advanced/customization.md'
- 'Worker Pools': 'advanced/worker-pools.md'