Start/stop particular EC2 instance from other EC2 instance in same AWS account

Question

What is a simple way to start/stop a particular (e.g. with hardcoded identifier) EC2 instance from another EC2 instance (running Node) in the same AWS account?

I am familiar with Node but not with AWS SDK, which I suppose I have to learn. At the same time I wonder whether there may be another AWS service in which I can more easily associate an HTTP resource (e.g. modifiable by credentialed PUT/DELETE) with the state (running/stopped) of particular EC2 instance.

Answer 1

You can do it with either the aws cli or the SDK.

AWS CLI

A very simple way is just to install the aws cli on the second instance and run

aws ec2 start-instances --instance-ids i-1234567890abcdef0

or

aws ec2 stop-instances --instance-ids i-1234567890abcdef0

---

SDK

If you want to stick with node, then you can start/stop an instance this way using the SDK:

 var params = {
  InstanceIds: [
     "i-1234567890abcdef0"
  ]
 };

 /* Start */
 ec2.startInstances(params, function(err, data) {
   if (err) console.log(err, err.stack); // an error occurred
   else     console.log(data);           // successful response
 });

 /* Stop */
 ec2.stopInstances(params, function(err, data) {
   if (err) console.log(err, err.stack); // an error occurred
   else     console.log(data);           // successful response
 });

---

Important note

Note that the instance's IAM role needs to include the following policy (or equivalent)

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Allow",
      "Action": [
        "ec2:StartInstances",
        "ec2:StopInstances"
      ],
      "Resource": "*"
    }
  ]
}

Hope it helps!