the variable "kubernetes_version" is not usable on module beta-private-cluster and safer-cluster

[maximeancellin]

TL;DR

Hi,

When you try to define a value in variable kubernetes_version on module safer-cluster. the value isn't used on plan.
Case tested with all type of release channel (UNSPECIFIED included).

Expected behavior

I would force to use an available version of GKE and decide when I want to upgrade the master of GKE.

I gave a specific version to do it and set the release channel to UNSPECIFIED.

Observed behavior

When I plan my configuration Terraform take the version latest of the current release channel.

Terraform Configuration

module "gke" {
  source  = "terraform-google-modules/kubernetes-engine/google//modules/safer-cluster"
  version = "21.0.0"

  kubernetes_version     = "1.21.11-gke.1100" #This value is ignored
  release_channel        = "UNSPECIFIED"

Configuration:

• Provider: registry.terraform.io/hashicorp/google
  Version: 4.22.0
• Provider: registry.terraform.io/hashicorp/google-beta
  Version: 4.22.0

### Terraform Version

```sh
v1.2.1

Additional information

We cannot choose the Kubernetes version we want to deploy or when we want to perform upgrade (or manually on the console but it's not a goal to do this if we use Terraform)

The issue seems similar like this one: #675

Thanks by advance for your support.

[pio2pio]

Also suffering from this issue in v21.1.0. Set CP to v1.21.x, I can see in the plan the version I want but version 1.22.x (default gcloud version) gets deployed.

[lyonsj]

As above, ver 21.1.0, make this module unusable for my purposes.

[jawnsy]

I ran into this problem as well, except I was using:

module "cluster" {
  source  = "terraform-google-modules/kubernetes-engine/google//modules/beta-private-cluster-update-variant"
  version = "20.0.0"

  kubernetes_version = "latest"
  release_channel    = "REGULAR"

The problem seems to be that setting release_channel results in the version being ignored:

terraform-google-kubernetes-engine/modules/beta-private-cluster-update-variant/cluster.tf

Line 62 in 774fc12

min_master_version = var.release_channel != null ? null : local.master_version

In my case, the resulting cluster version was the default version for new clusters (1.22.8) instead of the latest available (1.23.5) as I expected:

[pio2pio]

In v21.2.0 instead of using UNSPECIFIED I use release_channel = null. This has resulted of creating the control-plane with the version specified in ie. kubernetes_version = 1.21.12-gke.2200.

[kakarot291994]

By replacing the value release_channel=UNSPECIFIED with release_channel = null , I was able to set the desired version for my gke , Seems the logic on line 62 of cluster.tf min_master_version = var.release_channel != null ? null : local.master_version is the culprit for that .
After using the settings I am able to select the desired version .

Could there be any particular reason for this logic?

[bharathkkb]

Thanks for the report @maximeancellin and others. I merged a fix which should recognize UNSPECIFIED allowing to set a custom version.

[jawnsy]

@bharathkkb Awesome, thank you!

Since the UI allows us to select a channel (e.g. REGULAR) with a specific version (1.23), is it possible to do the same in the module? Or to set a minimum version constraint?

Otherwise, the only option will be to always use the oldest supported version of a given channel (or manually upgrade)

[uRhos]

@bharathkkb will there be a fix where you can select an actual release channel and the version from that channel like in the UI?

[jawnsy]

I've created this feature to track my request as it is separate from the original issue: #1356