Lambda to Start EC2 Instances on schedule and send instant public IP over email to multiple recipients using SNS

Following article will describe how to start EC2 Instances on schedule using Lambda and send the public IP  instantly to multiple recipients over email using SNS. This activity will help to schedule start EC2 instances on a particular time during weekdays and send the public IP of the instances to the development team who use those instances for some development purpose. Using this method you don’t have to allocate Elastic IP to the EC2 instances and also do not need any human intervention to send the public IP of the instances to users.

Step 1: Create following role for the EC2 Start Stop action:-

{

“Version”: “2012-10-17”,

“Statement”: [

{

“Effect”: “Allow”,

“Action”: [

“logs:CreateLogGroup”,

“logs:CreateLogStream”,

“logs:PutLogEvents”

],

“Resource”: “arn:aws:logs:*:*:*”

},

{

“Action”: “ec2:*”,

“Effect”: “Allow”,

“Resource”: “*”

}

]

}

Step 2: Create a lambda function with following Python 2.7 code:-

import boto3

region = ‘eu-central-1’

instances = [‘i- xxxxxxxxxxxx1′,’i- xxxxxxxxxxxx2′,’i- xxxxxxxxxxxx3’]

def lambda_handler(event, context):

ec2 = boto3.client(‘ec2’, region_name=region)

ec2.start_instances(InstanceIds=instances)

print ‘started Bastion and Store1 & Store2 servers’ + str(instances)

Step 3: Schedule the Lambda function from Cloudwatch -> rule -> schedule to run at 11AM IST from Monday to Friday

Step 4: Create another role in IAM with Full privilege on EC2 and on SNS (Not recommended for production. Be specific about granting privilages):-

Policy for EC2

{

“Version”: “2012-10-17”,

“Statement”: [

{

“Action”: “ec2:*”,

“Effect”: “Allow”,

“Resource”: “*”

}

]

}

Policy for SNS

{

“Version”: “2012-10-17”,

“Statement”: [

{

“Effect”: “Allow”,

“Action”: [

“sns:*”

],

“Resource”: “arn:aws:sns:eu-central-1:xxxxxxxxxx:fra_tcs_store_ips”

}

]

}

Step 5: Create new Lambda function with the above policy to fetch public IP of instances and send SNS notifications:-

from __future__ import print_function

import json

import boto3

ec2 = boto3.resource(‘ec2′, region_name=’eu-central-1’)

client = boto3.client(

“sns”,

aws_access_key_id=”**********************”,

aws_secret_access_key=”***********************”,

region_name=”eu-central-1″

)

 

topic = client.create_topic(Name=”storeipnotifications”)

topic_arn = topic[‘TopicArn’]

 

client.subscribe(TopicArn=topic_arn,Protocol=’email’,Endpoint=’email.1@xxxxx.com’)

client.subscribe(TopicArn=topic_arn,Protocol=’email’,Endpoint=’email.2@xxxxx.com’)

client.subscribe(TopicArn=topic_arn,Protocol=’email’,Endpoint=’email.3@xxxxxx.com’)

client.subscribe(TopicArn=topic_arn,Protocol=’email’,Endpoint=’email.4@xxxxxx.com’)

 

instances1 = ec2.instances.filter(Filters=[{‘Name’: ‘instance-id’, ‘Values’: [‘i-xxxxxxxxxxxx1’]}])

instances2 = ec2.instances.filter(Filters=[{‘Name’: ‘instance-id’, ‘Values’: [‘i- xxxxxxxxxxxx2’]}])

 

for instance in instances1:

store1IP = instance.public_ip_address

print(“Store1 public IP – “, instance.public_ip_address)

for instance in instances2:

store2IP = instance.public_ip_address

print(“Store2 public IP – “, instance.public_ip_address)

 

print(‘Loading function’)

 

def lambda_handler(event, context):

message = ‘Store1 IP:’+store1IP+’ , Store2 IP:’+store2IP

print(message)

client.publish(Message=message, TopicArn=topic_arn)

return message

Step 6: Now create the schedule to run this Lambda code at 11:05AM IST from Monday to Friday

So once the email subscription is confirmed by the recipients, the recipients will start receiving the IP address of the 2 Stores at 11:05AM IST from Monday to Friday.