chore!: change default distro image from CentOS 7 to Rocky Linux 9

Main motivation behind this is that CentOS 7 is reaching its end of life
on June 30, 2024 and Rocky Linux is strongly supported by Google Cloud Platform.

BREAKING CHANGE: replaces existing default value for instance_template module

examples/mig/full/variables.tf

@@ -75,17 +75,17 @@ variable "labels" {
 
 /* disk */
 variable "source_image" {
-  description = "Source disk image. If neither source_image nor source_image_family is specified, defaults to the latest public CentOS image."
+  description = "Source disk image. If neither source_image nor source_image_family is specified, defaults to the latest public Rocky Linux 9 optimized for GCP image."
   default     = ""
 }
 
 variable "source_image_family" {
-  description = "Source image family. If neither source_image nor source_image_family is specified, defaults to the latest public CentOS image."
+  description = "Source image family. If neither source_image nor source_image_family is specified, defaults to the latest public Rocky Linux 9 optimized for GCP image."
   default     = ""
 }
 
 variable "source_image_project" {
-  description = "Project where the source image comes from"
+  description = "Project where the source image comes from. The default project contains Rocky Linux images."
   default     = ""
 }
 
@@ -123,7 +123,6 @@ variable "additional_disks" {
   default = []
 }
 
-
 /* metadata */
 variable "startup_script" {
   description = "User startup script to run when instances spin up"

examples/umig/full/main.tf

@@ -15,7 +15,6 @@
  */
 
 provider "google" {
-
   project = var.project_id
   region  = var.region
 }

examples/umig/full/variables.tf

@@ -23,8 +23,6 @@ variable "project_id" {
   type        = string
 }
 
-
-
 variable "hostname" {
   description = "Hostname prefix for instances."
   default     = "default"
@@ -77,17 +75,17 @@ variable "labels" {
 
 /* disk */
 variable "source_image" {
-  description = "Source disk image. If neither source_image nor source_image_family is specified, defaults to the latest public CentOS image."
+  description = "Source disk image. If neither source_image nor source_image_family is specified, defaults to the latest public Rocky Linux 9 optimized for GCP image."
   default     = ""
 }
 
 variable "source_image_family" {
-  description = "Source image family. If neither source_image nor source_image_family is specified, defaults to the latest public CentOS image."
+  description = "Source image family. If neither source_image nor source_image_family is specified, defaults to the latest public Rocky Linux 9 optimized for GCP image."
   default     = ""
 }
 
 variable "source_image_project" {
-  description = "Project where the source image comes from"
+  description = "Project where the source image comes from. The default project contains Rocky Linux images."
   default     = ""
 }
 

modules/instance_template/README.md

@@ -44,9 +44,9 @@ See the [simple](../../examples/instance_template/simple) for a usage example.
 | resource\_policies | A list of self\_links of resource policies to attach to the instance. Modifying this list will cause the instance to recreate. Currently a max of 1 resource policy is supported. | `list(string)` | `[]` | no |
 | service\_account | Service account to attach to the instance. See https://www.terraform.io/docs/providers/google/r/compute_instance_template#service_account. | <pre>object({<br>    email  = string<br>    scopes = set(string)<br>  })</pre> | n/a | yes |
 | shielded\_instance\_config | Not used unless enable\_shielded\_vm is true. Shielded VM configuration for the instance. | <pre>object({<br>    enable_secure_boot          = bool<br>    enable_vtpm                 = bool<br>    enable_integrity_monitoring = bool<br>  })</pre> | <pre>{<br>  "enable_integrity_monitoring": true,<br>  "enable_secure_boot": true,<br>  "enable_vtpm": true<br>}</pre> | no |
-| source\_image | Source disk image. If neither source\_image nor source\_image\_family is specified, defaults to the latest public CentOS image. | `string` | `""` | no |
-| source\_image\_family | Source image family. If neither source\_image nor source\_image\_family is specified, defaults to the latest public CentOS image. | `string` | `"centos-7"` | no |
-| source\_image\_project | Project where the source image comes from. The default project contains CentOS images. | `string` | `"centos-cloud"` | no |
+| source\_image | Source disk image. If neither source\_image nor source\_image\_family is specified, defaults to the latest public Rocky Linux 9 optimized for GCP image. | `string` | `""` | no |
+| source\_image\_family | Source image family. If neither source\_image nor source\_image\_family is specified, defaults to the latest public Rocky Linux 9 optimized for GCP image. | `string` | `"rocky-linux-9-optimized-gcp"` | no |
+| source\_image\_project | Project where the source image comes from. The default project contains Rocky Linux images. | `string` | `"rocky-linux-cloud"` | no |
 | spot | Provision a SPOT instance | `bool` | `false` | no |
 | spot\_instance\_termination\_action | Action to take when Compute Engine preempts a Spot VM. | `string` | `"STOP"` | no |
 | stack\_type | The stack type for this network interface to identify whether the IPv6 feature is enabled or not. Values are `IPV4_IPV6` or `IPV4_ONLY`. Default behavior is equivalent to IPV4\_ONLY. | `string` | `null` | no |

modules/instance_template/main.tf

@@ -19,9 +19,9 @@
 #########
 
 locals {
-  source_image         = var.source_image != "" ? var.source_image : "centos-7-v20201112"
-  source_image_family  = var.source_image_family != "" ? var.source_image_family : "centos-7"
-  source_image_project = var.source_image_project != "" ? var.source_image_project : "centos-cloud"
+  source_image         = var.source_image != "" ? var.source_image : "rocky-linux-9-optimized-gcp-v20240111"
+  source_image_family  = var.source_image_family != "" ? var.source_image_family : "rocky-linux-9-optimized-gcp"
+  source_image_project = var.source_image_project != "" ? var.source_image_project : "rocky-linux-cloud"
 
   boot_disk = [
     {

modules/instance_template/metadata.yaml

@@ -260,17 +260,17 @@ spec:
           enable_secure_boot: true
           enable_vtpm: true
       - name: source_image
-        description: Source disk image. If neither source_image nor source_image_family is specified, defaults to the latest public CentOS image.
+        description: Source disk image. If neither source_image nor source_image_family is specified, defaults to the latest public Rocky Linux 9 optimized for GCP image.
         varType: string
         defaultValue: ""
       - name: source_image_family
-        description: Source image family. If neither source_image nor source_image_family is specified, defaults to the latest public CentOS image.
+        description: Source image family. If neither source_image nor source_image_family is specified, defaults to the latest public Rocky Linux 9 optimized for GCP image.
         varType: string
-        defaultValue: centos-7
+        defaultValue: rocky-linux-9-optimized-gcp
       - name: source_image_project
-        description: Project where the source image comes from. The default project contains CentOS images.
+        description: Project where the source image comes from. The default project contains Rocky Linux images.
         varType: string
-        defaultValue: centos-cloud
+        defaultValue: rocky-linux-cloud
       - name: spot
         description: Provision a SPOT instance
         varType: bool

modules/instance_template/variables.tf

@@ -119,21 +119,21 @@ variable "resource_policies" {
 # disk
 #######
 variable "source_image" {
-  description = "Source disk image. If neither source_image nor source_image_family is specified, defaults to the latest public CentOS image."
+  description = "Source disk image. If neither source_image nor source_image_family is specified, defaults to the latest public Rocky Linux 9 optimized for GCP image."
   type        = string
   default     = ""
 }
 
 variable "source_image_family" {
-  description = "Source image family. If neither source_image nor source_image_family is specified, defaults to the latest public CentOS image."
+  description = "Source image family. If neither source_image nor source_image_family is specified, defaults to the latest public Rocky Linux 9 optimized for GCP image."
   type        = string
-  default     = "centos-7"
+  default     = "rocky-linux-9-optimized-gcp"
 }
 
 variable "source_image_project" {
-  description = "Project where the source image comes from. The default project contains CentOS images."
+  description = "Project where the source image comes from. The default project contains Rocky Linux images."
   type        = string
-  default     = "centos-cloud"
+  default     = "rocky-linux-cloud"
 }
 
 variable "disk_size_gb" {

modules/preemptible_and_regular_instance_templates/README.md

@@ -26,9 +26,9 @@ See the [simple](../../examples/preemptible_and_regular_instance_templates/simpl
 | network | The name or self\_link of the network to attach this interface to. Use network attribute for Legacy or Auto subnetted networks and subnetwork for custom subnetted networks. | `string` | `""` | no |
 | project\_id | The GCP project ID | `string` | `null` | no |
 | service\_account | Service account to attach to the instance. See https://www.terraform.io/docs/providers/google/r/compute_instance_template#service_account. | <pre>object({<br>    email  = string<br>    scopes = set(string)<br>  })</pre> | n/a | yes |
-| source\_image | Source disk image. If neither source\_image nor source\_image\_family is specified, defaults to the latest public CentOS image. | `string` | `""` | no |
-| source\_image\_family | Source image family. If neither source\_image nor source\_image\_family is specified, defaults to the latest public CentOS image. | `string` | `""` | no |
-| source\_image\_project | Project where the source image comes from | `string` | `""` | no |
+| source\_image | Source disk image. If neither source\_image nor source\_image\_family is specified, defaults to the latest public Rocky Linux 9 optimized for GCP image. | `string` | `""` | no |
+| source\_image\_family | Source image family. If neither source\_image nor source\_image\_family is specified, defaults to the latest public Rocky Linux 9 optimized for GCP image. | `string` | `""` | no |
+| source\_image\_project | Project where the source image comes from. The default project contains Rocky Linux images. | `string` | `""` | no |
 | startup\_script | User startup script to run when instances spin up | `string` | `""` | no |
 | subnetwork | The name of the subnetwork to attach this interface to. The subnetwork must exist in the same region this instance will be created in. Either network or subnetwork must be provided. | `string` | `""` | no |
 | subnetwork\_project | The ID of the project in which the subnetwork belongs. If it is not provided, the provider project is used. | `string` | `""` | no |

modules/preemptible_and_regular_instance_templates/metadata.yaml

@@ -152,15 +152,15 @@ spec:
         defaultValue: null
         required: true
       - name: source_image
-        description: Source disk image. If neither source_image nor source_image_family is specified, defaults to the latest public CentOS image.
+        description: Source disk image. If neither source_image nor source_image_family is specified, defaults to the latest public Rocky Linux 9 optimized for GCP image.
         varType: string
         defaultValue: ""
       - name: source_image_family
-        description: Source image family. If neither source_image nor source_image_family is specified, defaults to the latest public CentOS image.
+        description: Source image family. If neither source_image nor source_image_family is specified, defaults to the latest public Rocky Linux 9 optimized for GCP image.
         varType: string
         defaultValue: ""
       - name: source_image_project
-        description: Project where the source image comes from
+        description: Project where the source image comes from. The default project contains Rocky Linux images.
         varType: string
         defaultValue: ""
       - name: startup_script

modules/preemptible_and_regular_instance_templates/variables.tf

@@ -54,19 +54,19 @@ variable "labels" {
 # disk
 #######
 variable "source_image" {
-  description = "Source disk image. If neither source_image nor source_image_family is specified, defaults to the latest public CentOS image."
+  description = "Source disk image. If neither source_image nor source_image_family is specified, defaults to the latest public Rocky Linux 9 optimized for GCP image."
   type        = string
   default     = ""
 }
 
 variable "source_image_family" {
-  description = "Source image family. If neither source_image nor source_image_family is specified, defaults to the latest public CentOS image."
+  description = "Source image family. If neither source_image nor source_image_family is specified, defaults to the latest public Rocky Linux 9 optimized for GCP image."
   type        = string
   default     = ""
 }
 
 variable "source_image_project" {
-  description = "Project where the source image comes from"
+  description = "Project where the source image comes from. The default project contains Rocky Linux images."
   type        = string
   default     = ""
 }