aws ssm automation

This blog will help you to deploy bash scripts or run linux commands on multiple servers at once.

Steps involved 

1. Create multiple EC2 machines 

2. Create IAM role for EC2 and attach SSM policy. 

3. Attach IAM role created in step 2 to EC2 machine 

4. Check in AWS SSM console if servers are showing or not in RUN command. 

5. Go to AWS SSM - select Run command and than select Shell script to run command on multiple linux machine at once 

6. Enter the bash script in the console 

7. Select the logs destination 

8. Deploy - check the in the console for status 

1. Create multiple EC2 machine 

Open the Amazon EC2 console at https://console.aws.amazon.com/ec2/.
Choose Launch Instance.
Choose an Amazon Machine Image (AMI), find an Amazon Linux 2 AMI at the top of the list and choose Select.
Choose an Instance Type, choose Next: Configure Instance Details.
Configure Instance Details, provide the following information:
Leave Number of instances at one.
Leave Purchasing option at the default setting.
For Network, choose the entry for the Default VPC
For Subnet, choose a default subnet in any Availability Zone.
Choose Next: Add Storage.
For File systems, choose EBS or leave the default option
Choose Next: Add Tags.
Name your instance and choose Next: 

Configure Security Group.
Configure Security Group, select port number 22 and port 80 in inbound and leave the outbound port as it is (port 80 require to check the apache server)
Select the keypair - create new keypair - name as per choice, download the keypair
Choose Review and Launch.
Choose Launch.

2. Create IAM role for EC2 and attach SSM policy. 

Open the IAM console at https://console.aws.amazon.com/iam/.

In the navigation pane, choose Roles, and then choose Create role.

Select EC2 and than click on next permission 

Search SSMfullaccess policy from the list 

Name your Role - for eg. ec2role-ssm

Finish 

3. Attach IAM role created in step 2 to EC2 machine 

go to the EC2 machine created in the step 1.

from the console - ec2 - select the machine - go to action - security - select IAM role 

attach the IAM role created in step 2 for eg. ec2role-ssm

save the settings 

4. Check in AWS SSM console if servers are showing or not in Run command. 

go to aws console - services - search for ssm 

select Run command from the left side menu 

look-up for the instance attached with SSM role 

If instance is not showing - check step 2 and step 3 again 

if still problem make sure to stop and start the machine 

5. Go to AWS SSM - select Run command and than select Shell script to run command on multiple linux machine at once 

go to aws console - services - search for ssm 

select Run command from the left side menu 

search for AWS-RunShellScript

6. Enter the bash script in the console 

click on run command 

select description 

select document version 

now in command parameter enter the shell script 

---this script will install apache server------

#!/bin/bash

yum install httpd -y

service httpd start

chkconfig httpd on

echo "aws ssm demo to deploy on multiple machines" > /var/www/html/index.html

leave working directory and execution timeout as default

in the Target select the machine manually 

In other parameter - update comments 

7. Select the logs destination 

enable s3 bucket for logs 

select the s3 bucket name 

enable cloudwatch logs 

8. Deploy - check the in the console for status 

click run and wait for the status 

if status is showing success 

copy the ec2 public address and paste in the browser to verify apache installed or not 

Troubleshoot

Make sure in the security group port number 22 and port number 80 allow in inbond

check the IAM permission for correct access

check for the S3 bucket permission 

-----------Ref script to check if apache service running or not --------------

#!/usr/bin/env bash

set -e

echo "Starting httpd..."

if [ -x "$(command -v systemctl)" ]; then

  echo "using systemctl"

  sudo systemctl enable httpd.service

  sudo systemctl start httpd

else

  echo "using upstart"

  sudo start httpd

fi