[preview] force gce when providing infrastructure, avoid harvester (#17475)

* [preview] force gce, no harvester

* [preview] default to using spot for GCE VMs

* [preview] bump sizes up now that we're using spot

...and actually use spot by changing the default for gce_use_spot

We'll address the disk pressure issues (which cause pods to evict on install, but eventually succeed) in a separate PR.

Author: kylos101

dev/preview/infrastructure/modules/gce/variables.tf

@@ -15,7 +15,7 @@ variable "preview_namespace" {
 
 variable "vm_type" {
   type    = string
-  default = "n2d-standard-8"
+  default = "n2d-standard-16"
 }
 
 variable "ssh_key" {
@@ -61,7 +61,7 @@ variable "gcp_project_dns" {
 
 variable "use_spot" {
   type        = bool
-  default     = false
+  default     = true
   description = "Flag to decide whether to use spot instances"
 }
 

dev/preview/infrastructure/modules/gce/vm.tf

@@ -80,5 +80,5 @@ locals {
     ssh_authorized_keys = var.ssh_key
   })
 
-  machine_type = var.with_large_vm ? "n2d-standard-16" : var.vm_type
+  machine_type = var.with_large_vm ? "n2d-standard-32" : var.vm_type
 }

dev/preview/infrastructure/variables.tf

@@ -29,7 +29,7 @@ variable "dev_kube_context" {
 
 variable "vm_type" {
   type    = string
-  default = "n2d-standard-8"
+  default = "n2d-standard-16"
 }
 
 variable "vm_image" {
@@ -52,7 +52,7 @@ variable "gcp_project_dns" {
 
 variable "gce_use_spot" {
   type        = bool
-  default     = false
+  default     = true
   description = "Flag to decide whether to use spot instances"
 }
 

dev/preview/workflow/preview/deploy-harvester.sh

@@ -33,7 +33,8 @@ shopt -os allexport
 
 terraform_init
 
-source "${SCRIPT_PATH}/determine-env.sh"
+# avoid harvester entirely
+export TF_VAR_infra_provider="gce"
 
 PLAN_EXIT_CODE=0
 terraform_plan || PLAN_EXIT_CODE=$?