Magic numbers of Amazon Web Services: 386209384616

One thing that amuses me when dealing with AWS is this number: 386209384616.

The number appears in this policy:

{
"Version": "2012-10-17",
"Statement": [
{
"Effect": "Allow",
"Principal": {
"AWS": "386209384616"
},
"Action": [
"s3:GetBucketAcl",
"s3:GetBucketPolicy"
],
"Resource": "arn:aws:s3:::bucketname"
},
{
"Effect": "Allow",
"Principal": {
"AWS": "386209384616"
},
"Action": "s3:PutObject",
"Resource": "arn:aws:s3:::bucketname/*"
}
]
}

This policy is given by AWS in this guideline to turn on AWS Cost and Usage Reports.

AWS offers the option to have your billing reports placed in a S3 bucket and it (as represented by 386209384616) needs permissions to put reports into the bucket. You can then use those reports to do further analysis. This is one of the main method used by Liquid Sky to obtain a user’s detailed bill for analysis.

While it seems normal to follow through applying such a policy to a bucket, there’s quite a number of things that came to mind:

1. Principal refers to the entity that is involved in the policy set. This can be a user, account, or service. By the look of it, 386209384616 seems to be an AWS account.

2. If it is an AWS account, it seems to imply that the account hosts the billing report generation process.

3. The permission also imply that AWS will perform a PUT action to place detailed bills onto the bucket (obviously 😬).

4. This can seemingly be corroborated with a line in our detailed bill, where we get a few line items relating to the PUT. I believe we get charged for the PUT requests, though the data transfer is free. The PUT requests charge for the purpose of bill dropping are sub-cents though.

5. AWS really dog-foods. Well, it isn’t even dog-fooding. They’re using what many modern companies already use currently.

6. It’s nice to see that AWS’ supporting services are ran pretty much the same way as how outside companies will run their workload within AWS. There’s a feeling of democracy, that all software/processes are equal within the AWS cloud (well, this is just from this particular observation anyway).

7. This should be how the cloud is ran, though it also seem like the AWS cloud itself being just a larger shared network resource. It’s a reminder that the cloud is still made of finite hardware in its physical eventuality.

8. At the same time, it really seems a bit weird that it is a number. From a developer’s eye, we will probably be expecting some form of named structure, like localhost, to reference the host.

Well, hope you had some fun reading this! If you have more magic number or quirky observations to share, do send them over via HN, Twitter or right here.