AWS CloudFormation and Windows Server 2008 R2 for Bootstrap file downloads

Question

AWS released a new AMI recently which has CloudFormation tools installed by default on their Windows Server 2008 R2. The AMI itself can be found here : [https://aws.amazon.com/amis/microsoft-windows-server-2008-r2-base-cloudformation]

When using this AMI directly within a CloudFormation template and launching the stack, I am able to launch my stack easily and the instance downloads my files located in S3 without any problem during boot up, all the folders created by cfn-init command can also be seen as expected.

However, if I modify the AMI to customize (just enabling IIS) it and recreate a new AMI and use this AMI within the template, the files don't get downloaded neither are the other folders suppose to be created by cfn-init command can be seen.

Any suggestions ?! Am I missing something ?!

Answer 1

Most probable cause of this is that the custom AMI was created without using EC2Config Service's Bundle tab.

CloudFormaion support on Windows depends on EC2Config service's functionality of running commands specified in User Data on first boot. This functionality automatically gets disabled after first boot so that the subsequent boots do not cause re-runs of the same commands.

If the custom AMI is created using EC2Config's Bundle tab , it ensures that the resulting AMI has the User Data command execution functionality enabled. Hence it is necessary (and always recommended) to create the custom AMI using EC2Config's Bundle tab.

Hope this helps.

Regards, Shon