Identity and Access Management (AWS IAM) is one of the first services you are introduced to when learning about AWS.<\/a><\/p>\n\n\n\n
Everyone shouldn’t have access to everything.<\/p>\n\n\n\n
Exactly what you think of when you think of users in the real world.<\/p>\n\n\n\n
If you are setting up as AWS account for the first time you will begin with the root user and full administrative rights. Your first step should be creating a new user rather than using the root user for day to day activities. <\/p>\n\n\n\n
Users can have any combination of credentials:<\/p>\n\n\n\n
Default limits:<\/p>\n\n\n\n
A collection of users. Just like in the real world this could be a group of marketing users who need access to campaign data, finance users who need more sensitive data or customer services users who need customer data.<\/p>\n\n\n\n
Default limits:<\/p>\n\n\n\n
This is what defines the set of permissions<\/a> your users and services have. This where you decide if the ‘marketing’ role needs to be able to read\/write to an S3 bucket<\/a>, read\/write to the RDS<\/a>, and nothing else.<\/p>\n\n\n\n
When they are first created users have no permissions. These are added by creating and attaching policies.<\/p>\n\n\n\n
Policies come in three different forms:<\/p>\n\n\n\n
Managed Policies<\/strong> – policies provided by AWS and cannot be edited.
Customer Managed Policies<\/strong> – policies created by the customer, which you can edit.
Inline Policies<\/strong> – policies which are directly attached to a user.<\/p>\n\n\n\n
These can be created through the AWS Console using the predefined policy documents or using JSON to define these on a case-by-case basis when you can’t get what you need through the predefined policies.<\/p>\n\n\n\n
Default limit of:<\/p>\n\n\n\n
Policies can be created either using the UI or by writing JSON with what you need.<\/p>\n\n\n\n
If you choose to write, or finely tune your policy using JSON AWS has a tool<\/a> that can be used to make this simpler. Even if you do not choose to use it it can be a useful way to illustrate what goes into a policy.<\/p>\n\n\n\n
There are three parts to the policy at it’s most basic level:<\/p>\n\n\n\n
The current version of the policy language.<\/p>\n\n\n\n
In this case to Create and Delete buckets<\/p>\n\n\n\n
In this case to ‘Allow’. This is by default set to ‘Deny’ in the same way that Users have no permissions by default when they are created.<\/p>\n\n\n\n
The syntax here is used to determine to ARN or Amazon Resource Name. In this case ‘my_new_bucket’ in S3<\/p>\n\n\n\n
{\n \"Version\": \"2012-10-17\",\n \"Statement\": [\n {\n Action\": [\n \"s3:CreateBucket\",\n \"s3:DeleteBucket\"\n ],\n \"Effect\": \"Allow\",\n \"Resource\": \"arn:aws:s3:::my_new_bucket\"\n }\n ]\n}\n<\/code><\/pre>\n\n\n\n
\n\n\n\nTroubleshooting<\/h2>\n\n\n\n
- Not all services use AWS IAM so check out the restrictions<\/a><\/li>
- It’s important to test that the policies are doing what you think they are. Along with the tool to build your policies, AWS offers a simulator<\/a> that will test your policy will do what is expected. There is a bit of set up involved but it’s well worth it to make sure you are granting the right level of access to your users.<\/li>
- The biggest challenge with AWS IAM is determining who needs access to what before you start creating policies. Take time to plan what your users are likely to need, and not need, to follow the principle of least privilege. But allow for some flexibility if privileges need to be elevated in future.<\/li><\/ul>\n\n\n\n
\n\n\n\nUseful Links<\/h2>\n\n\n\n
AWS IAM Documentation<\/a>
FAQ<\/a>
Policy Builder<\/a>
JSON Reference Guide<\/a>
Testing Policies Documentation<\/a>
Policy Test Simulator<\/a><\/p>\n\n\n\n
\n\n\n\nPhoto by Markus Spiske temporausch.com<\/a><\/strong> from Pexels<\/a><\/strong> <\/p>\n","protected":false},"excerpt":{"rendered":"