initial commit, aws-asg example

examples/aws-asg/README.md

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+# ASG example
+
+This example shows how to launch instances using Auto Scaling Groups.
+
+This creates a security group, launch configuration, auto scaling group and an ELB. The user data for launch configuration installs nginx and it listnes on port 80.
+
+The example uses latest Ubuntu AMIs. 
+
+Make sure you change the list of availability zones that is applicable to your account and region.
+
+To run, configure your AWS provider as described in https://www.terraform.io/docs/providers/aws/index.html
+
+Running the example
+
+For planning phase 
+
+terraform plan  -var 'key_name={your_key_name}}'
+
+For apply phase 
+
+terraform apply  -var 'key_name={your_key_name}}'
+
+Once the stack is created, wait for few minsutes and test the stack by launching a browser with ELB url. 
+
+To remove the stack
+
+terraform apply  -var 'key_name={your_key_name}}'
+

examples/aws-asg/main.tf

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+# Specify the provider and access details
+provider "aws" {
+    region = "${var.aws_region}"
+}
+
+resource "aws_elb" "web-elb" {
+  name = "terraform-example-elb"
+
+  # The same availability zone as our instances
+  availability_zones = ["${split(",", var.availability_zones)}"]
+  listener {
+    instance_port = 80
+    instance_protocol = "http"
+    lb_port = 80
+    lb_protocol = "http"
+  }
+
+  health_check {
+    healthy_threshold = 2
+    unhealthy_threshold = 2
+    timeout = 3
+    target = "HTTP:80/"
+    interval = 30
+  }
+
+}
+
+resource "aws_autoscaling_group" "web-asg" {
+  availability_zones = ["${split(",", var.availability_zones)}"]
+  name = "terraform-example-asg"
+  max_size = "${var.asg_max}"
+  min_size = "${var.asg_min}"
+  desired_capacity = "${var.asg_desired}"
+  force_delete = true
+  launch_configuration = "${aws_launch_configuration.web-lc.name}"
+  load_balancers = ["${aws_elb.web-elb.name}"]
+  #vpc_zone_identifier = ["${split(",", var.availability_zones)}"]
+  tag {
+        key = "Name"
+        value = "web-asg"
+        propagate_at_launch = "true"
+    }
+  }
+
+resource "aws_launch_configuration" "web-lc" {
+    name = "terraform-example-lc"
+    image_id = "${lookup(var.aws_amis, var.aws_region)}"
+    instance_type = "${var.instance_type}"
+    # Security group
+    security_groups = ["${aws_security_group.default.name}"]
+    user_data = "${file("userdata.sh")}"
+    key_name = "${var.key_name}"
+}
+
+# Our default security group to access
+# the instances over SSH and HTTP
+resource "aws_security_group" "default" {
+    name = "terraform_example_sg"
+    description = "Used in the terraform"
+
+    # SSH access from anywhere
+    ingress {
+        from_port = 22
+        to_port = 22
+        protocol = "tcp"
+        cidr_blocks = ["0.0.0.0/0"]
+    }
+
+    # HTTP access from anywhere
+    ingress {
+        from_port = 80
+        to_port = 80
+        protocol = "tcp"
+        cidr_blocks = ["0.0.0.0/0"]
+    }
+
+    # outbound internet access
+    egress {
+        from_port = 0
+        to_port = 0
+        protocol = "-1"
+        cidr_blocks = ["0.0.0.0/0"]
+    }
+}

examples/aws-asg/outputs.tf

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+output "security_group" {
+    value = "${aws_security_group.default.id}"
+}
+output "launch_configuration" {
+    value = "${aws_launch_configuration.web-lc.id}"
+}
+output "asg_name" {
+    value = "${aws_autoscaling_group.web-asg.id}"
+}
+output "elb_name" {
+    value = "${aws_elb.web-elb.dns_name}"
+}

examples/aws-asg/userdata.sh

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+#!/bin/bash -v
+apt-get update -y
+apt-get install -y nginx > /tmp/nginx.log

examples/aws-asg/variables.tf

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+variable "aws_region" {
+    description = "The AWS region to create things in."
+    default = "us-east-1"
+}
+
+# Ubuntu Precise 12.04 LTS (x64)
+variable "aws_amis" {
+    default = {
+        "us-east-1" = "ami-5f709f34"
+        "us-west-2" = "ami-7f675e4f"
+    }
+}
+
+variable "availability_zones" {
+	default = "us-east-1b,us-east-1c,us-east-1d,us-east-1e"
+    description = "List of availability zones, use AWS CLI to find your "
+}
+
+variable "key_name" {
+    description = "Name of AWS key pair"
+}
+
+variable "instance_type" {
+    default = "t2.micro"
+    description = "AWS instance type"
+}
+
+variable "asg_min" {
+    description = "Min numbers of servers in ASG"
+    default = "1"
+}
+
+variable "asg_max" {
+    description = "Max numbers of servers in ASG"
+    default = "2"
+}
+
+variable "asg_desired" {
+    description = "Desired numbers of servers in ASG"
+    default = "1"
+}