fix(misc): contrib/terraform/aws (#7818)

* fix(misc): terraform/aws

- handles deployment with a single availability zone
- handles deployment with more than two availability zone
- handles etcd collocation with control-plane nodes (`aws_etcd_num=0`)
- allows to set a bastion instances count (`aws_bastion_num`)
- allows to set bastion/etcd/control-plane/workers rootfs volume size
- removes variables from terraform.tfvars that were not re-used
- adds .terraform.lock.hcl to .gitignore
- changes/updates base image from ubuntu-18.03 to debian-10

tested by a few coworkers of mine, and myself: thanks for the outstanding
work, on both those terraform samples and kubespray playbooks.
I did not test ubuntu deployments, I could still swap from buster to
focal. LMK.

* fix(gitlab-ci)

AFAIU, terraform.tfvars indentation should be fixed for / no diff
returned running `terraform fmt -check -diff`

https://gitlab.com/kargo-ci/kubernetes-sigs-kubespray/-/jobs/1445622114

contrib/terraform/aws/.gitignore

@@ -1,2 +1,3 @@
 *.tfstate*
+.terraform.lock.hcl
 .terraform

contrib/terraform/aws/create-infrastructure.tf

@@ -20,7 +20,7 @@ module "aws-vpc" {
 
   aws_cluster_name         = var.aws_cluster_name
   aws_vpc_cidr_block       = var.aws_vpc_cidr_block
-  aws_avail_zones          = slice(data.aws_availability_zones.available.names, 0, 2)
+  aws_avail_zones          = slice(data.aws_availability_zones.available.names, 0, length(var.aws_cidr_subnets_public) <= length(data.aws_availability_zones.available.names) ? length(var.aws_cidr_subnets_public) : length(data.aws_availability_zones.available.names))
   aws_cidr_subnets_private = var.aws_cidr_subnets_private
   aws_cidr_subnets_public  = var.aws_cidr_subnets_public
   default_tags             = var.default_tags
@@ -31,7 +31,7 @@ module "aws-elb" {
 
   aws_cluster_name      = var.aws_cluster_name
   aws_vpc_id            = module.aws-vpc.aws_vpc_id
-  aws_avail_zones       = slice(data.aws_availability_zones.available.names, 0, 2)
+  aws_avail_zones       = slice(data.aws_availability_zones.available.names, 0, length(var.aws_cidr_subnets_public) <= length(data.aws_availability_zones.available.names) ? length(var.aws_cidr_subnets_public) : length(data.aws_availability_zones.available.names))
   aws_subnet_ids_public = module.aws-vpc.aws_subnet_ids_public
   aws_elb_api_port      = var.aws_elb_api_port
   k8s_secure_api_port   = var.k8s_secure_api_port
@@ -52,9 +52,9 @@ module "aws-iam" {
 resource "aws_instance" "bastion-server" {
   ami                         = data.aws_ami.distro.id
   instance_type               = var.aws_bastion_size
-  count                       = length(var.aws_cidr_subnets_public)
+  count                       = var.aws_bastion_num
   associate_public_ip_address = true
-  availability_zone           = element(slice(data.aws_availability_zones.available.names, 0, 2), count.index)
+  availability_zone           = element(slice(data.aws_availability_zones.available.names, 0, length(var.aws_cidr_subnets_public) <= length(data.aws_availability_zones.available.names) ? length(var.aws_cidr_subnets_public) : length(data.aws_availability_zones.available.names)), count.index)
   subnet_id                   = element(module.aws-vpc.aws_subnet_ids_public, count.index)
 
   vpc_security_group_ids = module.aws-vpc.aws_security_group
@@ -79,11 +79,15 @@ resource "aws_instance" "k8s-master" {
 
   count = var.aws_kube_master_num
 
-  availability_zone = element(slice(data.aws_availability_zones.available.names, 0, 2), count.index)
+  availability_zone = element(slice(data.aws_availability_zones.available.names, 0, length(var.aws_cidr_subnets_public) <= length(data.aws_availability_zones.available.names) ? length(var.aws_cidr_subnets_public) : length(data.aws_availability_zones.available.names)), count.index)
   subnet_id         = element(module.aws-vpc.aws_subnet_ids_private, count.index)
 
   vpc_security_group_ids = module.aws-vpc.aws_security_group
 
+  root_block_device {
+    volume_size = var.aws_kube_master_disk_size
+  }
+
   iam_instance_profile = module.aws-iam.kube_control_plane-profile
   key_name             = var.AWS_SSH_KEY_NAME
 
@@ -106,11 +110,15 @@ resource "aws_instance" "k8s-etcd" {
 
   count = var.aws_etcd_num
 
-  availability_zone = element(slice(data.aws_availability_zones.available.names, 0, 2), count.index)
+  availability_zone = element(slice(data.aws_availability_zones.available.names, 0, length(var.aws_cidr_subnets_public) <= length(data.aws_availability_zones.available.names) ? length(var.aws_cidr_subnets_public) : length(data.aws_availability_zones.available.names)), count.index)
   subnet_id         = element(module.aws-vpc.aws_subnet_ids_private, count.index)
 
   vpc_security_group_ids = module.aws-vpc.aws_security_group
 
+  root_block_device {
+    volume_size = var.aws_etcd_disk_size
+  }
+
   key_name = var.AWS_SSH_KEY_NAME
 
   tags = merge(var.default_tags, tomap({
@@ -126,11 +134,15 @@ resource "aws_instance" "k8s-worker" {
 
   count = var.aws_kube_worker_num
 
-  availability_zone = element(slice(data.aws_availability_zones.available.names, 0, 2), count.index)
+  availability_zone = element(slice(data.aws_availability_zones.available.names, 0, length(var.aws_cidr_subnets_public) <= length(data.aws_availability_zones.available.names) ? length(var.aws_cidr_subnets_public) : length(data.aws_availability_zones.available.names)), count.index)
   subnet_id         = element(module.aws-vpc.aws_subnet_ids_private, count.index)
 
   vpc_security_group_ids = module.aws-vpc.aws_security_group
 
+  root_block_device {
+    volume_size = var.aws_kube_worker_disk_size
+  }
+
   iam_instance_profile = module.aws-iam.kube-worker-profile
   key_name             = var.AWS_SSH_KEY_NAME
 
@@ -152,10 +164,10 @@ data "template_file" "inventory" {
     public_ip_address_bastion = join("\n", formatlist("bastion ansible_host=%s", aws_instance.bastion-server.*.public_ip))
     connection_strings_master = join("\n", formatlist("%s ansible_host=%s", aws_instance.k8s-master.*.private_dns, aws_instance.k8s-master.*.private_ip))
     connection_strings_node   = join("\n", formatlist("%s ansible_host=%s", aws_instance.k8s-worker.*.private_dns, aws_instance.k8s-worker.*.private_ip))
-    connection_strings_etcd   = join("\n", formatlist("%s ansible_host=%s", aws_instance.k8s-etcd.*.private_dns, aws_instance.k8s-etcd.*.private_ip))
     list_master               = join("\n", aws_instance.k8s-master.*.private_dns)
     list_node                 = join("\n", aws_instance.k8s-worker.*.private_dns)
-    list_etcd                 = join("\n", aws_instance.k8s-etcd.*.private_dns)
+    connection_strings_etcd   = join("\n", formatlist("%s ansible_host=%s", ((var.aws_etcd_num > 0) ? (aws_instance.k8s-etcd.*.private_dns) : (aws_instance.k8s-master.*.private_dns)), ((var.aws_etcd_num > 0) ? (aws_instance.k8s-etcd.*.private_ip) : (aws_instance.k8s-master.*.private_ip))))
+    list_etcd                 = join("\n", ((var.aws_etcd_num > 0) ? (aws_instance.k8s-etcd.*.private_dns) : (aws_instance.k8s-master.*.private_dns)))
     elb_api_fqdn              = "apiserver_loadbalancer_domain_name=\"${module.aws-elb.aws_elb_api_fqdn}\""
   }
 }

contrib/terraform/aws/output.tf

@@ -11,7 +11,7 @@ output "workers" {
 }
 
 output "etcd" {
-  value = join("\n", aws_instance.k8s-etcd.*.private_ip)
+  value = join("\n", ((var.aws_etcd_num > 0) ? (aws_instance.k8s-etcd.*.private_ip) : (aws_instance.k8s-master.*.private_ip)))
 }
 
 output "aws_elb_api_fqdn" {

contrib/terraform/aws/sample-inventory/cluster.tfvars

@@ -9,6 +9,8 @@ aws_cidr_subnets_private = ["10.250.192.0/20", "10.250.208.0/20"]
 aws_cidr_subnets_public = ["10.250.224.0/20", "10.250.240.0/20"]
 
 #Bastion Host
+aws_bastion_num = 1
+
 aws_bastion_size = "t2.medium"
 
 #Kubernetes Cluster
@@ -17,22 +19,26 @@ aws_kube_master_num = 3
 
 aws_kube_master_size = "t2.medium"
 
+aws_kube_master_disk_size = 50
+
 aws_etcd_num = 3
 
 aws_etcd_size = "t2.medium"
 
+aws_etcd_disk_size = 50
+
 aws_kube_worker_num = 4
 
 aws_kube_worker_size = "t2.medium"
 
+aws_kube_worker_disk_size = 50
+
 #Settings AWS ELB
 
 aws_elb_api_port = 6443
 
 k8s_secure_api_port = 6443
 
-kube_insecure_apiserver_address = "0.0.0.0"
-
 default_tags = {
   #  Env = "devtest"  #  Product = "kubernetes"
 }

contrib/terraform/aws/templates/inventory.tpl

@@ -10,19 +10,18 @@ ${public_ip_address_bastion}
 [kube_control_plane]
 ${list_master}
 
-
 [kube_node]
 ${list_node}
 
-
 [etcd]
 ${list_etcd}
 
+[calico_rr]
 
 [k8s_cluster:children]
 kube_node
 kube_control_plane
-
+calico_rr
 
 [k8s_cluster:vars]
 ${elb_api_fqdn}

contrib/terraform/aws/terraform.tfvars

@@ -6,26 +6,34 @@ aws_vpc_cidr_block       = "10.250.192.0/18"
 aws_cidr_subnets_private = ["10.250.192.0/20", "10.250.208.0/20"]
 aws_cidr_subnets_public  = ["10.250.224.0/20", "10.250.240.0/20"]
 
-#Bastion Host
-aws_bastion_size = "t2.medium"
+# single AZ deployment
+#aws_cidr_subnets_private = ["10.250.192.0/20"]
+#aws_cidr_subnets_public  = ["10.250.224.0/20"]
 
+# 3+ AZ deployment
+#aws_cidr_subnets_private = ["10.250.192.0/24","10.250.193.0/24","10.250.194.0/24","10.250.195.0/24"]
+#aws_cidr_subnets_public  = ["10.250.224.0/24","10.250.225.0/24","10.250.226.0/24","10.250.227.0/24"]
+
+#Bastion Host
+aws_bastion_num  = 1
+aws_bastion_size = "t3.small"
 
 #Kubernetes Cluster
+aws_kube_master_num       = 3
+aws_kube_master_size      = "t3.medium"
+aws_kube_master_disk_size = 50
 
-aws_kube_master_num  = 3
-aws_kube_master_size = "t2.medium"
+aws_etcd_num       = 0
+aws_etcd_size      = "t3.medium"
+aws_etcd_disk_size = 50
 
-aws_etcd_num  = 3
-aws_etcd_size = "t2.medium"
-
-aws_kube_worker_num  = 4
-aws_kube_worker_size = "t2.medium"
+aws_kube_worker_num       = 4
+aws_kube_worker_size      = "t3.medium"
+aws_kube_worker_disk_size = 50
 
 #Settings AWS ELB
-
-aws_elb_api_port                = 6443
-k8s_secure_api_port             = 6443
-kube_insecure_apiserver_address = "0.0.0.0"
+aws_elb_api_port    = 6443
+k8s_secure_api_port = 6443
 
 default_tags = {
   #  Env = "devtest"

contrib/terraform/aws/terraform.tfvars.example

@@ -8,25 +8,26 @@ aws_cidr_subnets_public = ["10.250.224.0/20","10.250.240.0/20"]
 aws_avail_zones = ["eu-central-1a","eu-central-1b"]
 
 #Bastion Host
-aws_bastion_ami = "ami-5900cc36"
-aws_bastion_size = "t2.small"
-
+aws_bastion_num = 1
+aws_bastion_size = "t3.small"
 
 #Kubernetes Cluster
-
 aws_kube_master_num = 3
-aws_kube_master_size = "t2.medium"
+aws_kube_master_size = "t3.medium"
+aws_kube_master_disk_size = 50
 
 aws_etcd_num = 3
-aws_etcd_size = "t2.medium"
+aws_etcd_size = "t3.medium"
+aws_etcd_disk_size = 50
 
 aws_kube_worker_num = 4
-aws_kube_worker_size = "t2.medium"
-
-aws_cluster_ami = "ami-903df7ff"
+aws_kube_worker_size = "t3.medium"
+aws_kube_worker_disk_size = 50
 
 #Settings AWS ELB
-
 aws_elb_api_port = 6443
 k8s_secure_api_port = 6443
-kube_insecure_apiserver_address = 0.0.0.0
+
+default_tags = { }
+
+inventory_file = "../../../inventory/hosts"

contrib/terraform/aws/variables.tf

@@ -25,7 +25,7 @@ data "aws_ami" "distro" {
 
   filter {
     name   = "name"
-    values = ["ubuntu/images/hvm-ssd/ubuntu-bionic-18.04-amd64-server-*"]
+    values = ["debian-10-amd64-*"]
   }
 
   filter {
@@ -33,7 +33,7 @@ data "aws_ami" "distro" {
     values = ["hvm"]
   }
 
-  owners = ["099720109477"] # Canonical
+  owners = ["136693071363"] # Debian-10
 }
 
 //AWS VPC Variables
@@ -63,10 +63,18 @@ variable "aws_bastion_size" {
 * The number should be divisable by the number of used
 * AWS Availability Zones without an remainder.
 */
+variable "aws_bastion_num" {
+  description = "Number of Bastion Nodes"
+}
+
 variable "aws_kube_master_num" {
   description = "Number of Kubernetes Master Nodes"
 }
 
+variable "aws_kube_master_disk_size" {
+  description = "Disk size for Kubernetes Master Nodes (in GiB)"
+}
+
 variable "aws_kube_master_size" {
   description = "Instance size of Kube Master Nodes"
 }
@@ -75,6 +83,10 @@ variable "aws_etcd_num" {
   description = "Number of etcd Nodes"
 }
 
+variable "aws_etcd_disk_size" {
+  description = "Disk size for etcd Nodes (in GiB)"
+}
+
 variable "aws_etcd_size" {
   description = "Instance size of etcd Nodes"
 }
@@ -83,6 +95,10 @@ variable "aws_kube_worker_num" {
   description = "Number of Kubernetes Worker Nodes"
 }
 
+variable "aws_kube_worker_disk_size" {
+  description = "Disk size for Kubernetes Worker Nodes (in GiB)"
+}
+
 variable "aws_kube_worker_size" {
   description = "Instance size of Kubernetes Worker Nodes"
 }