adding variable for number of instances in ASG

main.tf

@@ -27,6 +27,11 @@ variable "key_name" {
   default     = "Bastion"
 }
 
+variable "bastion_instances" {
+  description = "Number of instances in the ASG"
+  default     = "1"
+}
+
 resource "aws_security_group" "bastion" {
   name        = "Bastion"
   vpc_id      = "${var.vpc_id}"
@@ -88,9 +93,9 @@ resource "aws_autoscaling_group" "bastion" {
   availability_zones   = ["${var.availability_zones}"]
   vpc_zone_identifier  = ["${var.subnet_ids}"]
   launch_configuration = "${aws_launch_configuration.bastion.id}"
-  min_size             = "1"
-  max_size             = "1"
-  desired_capacity     = "1"
+  min_size             = "${var.bastion_instances}"
+  max_size             = "${var.bastion_instances}"
+  desired_capacity     = "${var.bastion_instances}"
 
   tag {
     key = "Name"
@@ -111,4 +116,4 @@ resource "aws_autoscaling_group" "bastion" {
 #############################################################################################################
 output "security_group" {
     value = "${aws_security_group.bastion.id}"
-}
\ No newline at end of file
+}