Useful AWS commands

• aws iam list-users
• Gets a list of users in the AWS account. Returns full details of the user object.
• aws iam list-users --query Users[*].UserName
• Gets a list of user names in the account.
• aws iam list-policies 
• Returns a full list of of AWS policies which includes AWS managed and customer defined.
• aws iam get-account-password-policy
• Returns the password policy of the account. If none defined, returns "NoSuchEntity" error.
• aws iam get-account-summary
• Returns the limits of the account. Useful to find out what the limits and request increase from AWS support.
• aws iam list-policies --only-attached
• Returns a list of policies that are attached. Useful to find out what policies are being used.
• aws iam list-policies --only-attached --scope Local
• Gets a list of policies that are managed by the customer that are attached (ignoring AWS managed ones). Useful to detect how many customer defined policies are being used.
• aws iam list-entities-for-policy --policy-arn "ARN"
• Lists the users, groups, roles and resources that are using the given policy. 
• aws ec2 describe-regions
• Returns a list of regions available. In order for this command to work the "region" in the CLI. If the "region" is not specified we can use "aws configure" to configure a region.