General

Q: What is AWS Config?

AWS Config is a fully managed service that provides you with an AWS resource inventory, configuration history, and configuration change notifications to enable security and governance. With AWS Config you can discover existing AWS resources, export a complete inventory of your AWS resources with all configuration details, and determine how a resource was configured at any point in time. These capabilities enable compliance auditing, security analysis, resource change tracking, and troubleshooting.

Q: What are the benefits of AWS Config?

AWS Config makes it easy to track your resource’s configuration without the need for up-front investments and avoiding the complexity of installing and updating agents for data collection or maintaining large databases. Once you enable AWS Config, you can view continuously updated details of all configuration attributes associated with AWS resources. You are notified via Amazon Simple Notification Service (SNS) of every configuration change.

Q: How can AWS Config help with audits?

AWS Config gives you access to resource configuration history. You can relate configuration changes with AWS CloudTrail events that possibly contributed to the change in configuration. This information provides you full visibility, right from details, such as “Who made the change?”, “From what IP address?” to the effect of this change on AWS resources and related resources. You can use this information to generate reports to aid auditing and assessing compliance over a period of time.

Q: Who should use AWS Config?

AWS Config gives you access to resource configuration history. You can relate configuration changes with AWS CloudTrail events that possibly contributed to the change in configuration. This information provides you full visibility, right from details, such as “Who made the change?”, “From what IP address?” to the effect of this change on AWS resources and related resources. You can use this information to generate reports to aid auditing and assessing compliance over a period of time.

Q: How does AWS Config work with AWS CloudTrail?

AWS CloudTrail records user API activity on your account and allows you to access information about this activity. You get full details about API actions, such as identity of the caller, the time of the API call, the request parameters, and the response elements returned by the AWS service. AWS Config records point-in-time configuration details for your AWS resources as Configuration Items (CIs). You can use a CI to answer “What did my AWS resource look like?” at a point in time. You can use AWS CloudTrail to answer “Who made an API call to modify this resource?” For example, you can use the AWS Management Console for AWS Config to detect security group “Production-DB” was incorrectly configured in the past. Using the integrated AWS CloudTrail information, you can pinpoint which user misconfigured “Production-DB” security group.

Getting started

Q: How do I get started with this service?

The quickest way to get started with AWS Config is to use the AWS Management Console. You can turn on AWS Config in a few clicks. For additional details, see the Getting Started documentation.

Q: How do I access my resources’ configuration?

You can lookup current and historical resource configuration using the AWS Management Console, AWS Command Line Interface or SDKs.

For additional details, please refer to AWS Config documentation.

Q: Do I turn on AWS Config regionally or globally?

You turn on AWS Config on a per-region basis for your account.

Q: Can AWS Config aggregate data across different AWS accounts?

Yes, you can set up AWS Config to deliver configuration updates from different accounts to one S3 bucket, once the appropriate IAM policies are applied to the S3 bucket. You can also publish notifications to the one SNS Topic, within the same region, once appropriate IAM policies are applied to the SNS Topic.

Q: Is API activity on AWS Config itself logged by AWS CloudTrail?

Yes. All AWS Config API activity, including use of AWS Config APIs to read configuration data, is logged by AWS CloudTrail.

Q: What time and timezones are displayed in the timeline view of a resource? What about daylight savings?

AWS Config displays the time at which Configuration Items (CIs) were recorded for a resource on a timeline. All times are captured in Coordinated Universal Time (UTC). When the timeline is visualized on the management console, the services uses the current time zone (adjusted for daylight savings, if relevant) to display all times in the timeline view.

Resource configuration

Q: What is a configuration item?

A Configuration Item (CI) is the configuration of a resource at a given point-in-time. A CI consists of 5 sections:

  1. Basic information about the resource that is common across different resource types (e.g., Amazon Resource Names, tags),
  2. Configuration data specific to the resource (e.g., EC2 instance type),
  3. Map of relationships with other resources (e.g., EC2::Volume vol-3434df43 is “attached to instance” EC2 Instance i-3432ee3a),
  4. AWS CloudTrail event IDs that are related to this state,
  5. Metadata that helps you identify information about the CI, such as the version of this CI, and when this CI was captured.

Learn more about configuration items

Q: What are AWS Config relationships and how are they used?

AWS Config takes the relationships among resources into account when recording changes. For example, if a new Amazon EC2 Security Group is associated with an Amazon EC2 Instance, AWS Config records the updated configurations of both the primary resource, the Amazon EC2 Security Group, and related resources, such as the Amazon EC2 Instance, if these resources actually changed.

Q: Does AWS Config record every state a resource has been in?

AWS Config detects change to resource's configuration and records the configuration state that resulted from that change. In cases where several configuration changes are made to a resource in quick succession (e.g. within a span of few minutes), Config will only record the latest configuration of that resource that represents cumulative impact of the set of changes. In these situations, Config will only list the latest change in the relatedEvents field of the Configuration Item.This allows users and programs to continue to change infrastructure configurations without having to wait for Config to record intermediate transient states.

Q: Does AWS Config record configuration changes that did not result from API activity on that resource?

Yes, AWS Config will regularly scan configuration of resources for changes that haven't yet been recorded and record these changes. CIs recorded from these scans will not have a relatedEvent field in the payload, and only the latest state that is different from the state already recorded is picked up.

Config Rules

Q: What is a resource’s configuration?

Configuration of a resource is defined by the data included in the Configuration Item (CI) of AWS Config. The initial release of Config Rules makes the CI for a resource available to relevant rules. Config Rules can use this information along with any other relevant information such as other attached resource, business hours, etc. to evaluate compliance of a resource’s configuration.

Q: What is a rule?

A rule represents desired Configuration Item (CI) attribute values for resources and are evaluated by comparing those attribute values with CIs recorded by AWS Config. There are two types of rules:

AWS managed rules: AWS managed rules are pre-built and managed by AWS. You simply choose the rule you want to enable, then supply a few configuration parameters to get started.

Customer managed rules: Customer managed rules are custom rules, defined and built by you. You can create a function in AWS Lambda that can be invoked as part of a custom rule and these functions execute in your account.

The quickest way to get started with AWS Config is to use the AWS Management Console. You can turn on AWS Config in a few clicks. For additional details, see the documentation.

Q: How are rules created?

Rules are typically set up by the AWS account administrator. They can be created by leveraging AWS managed rules – a predefined set of rules provided by AWS or through customer managed rules. With AWS managed rules updates to the rule are automatically applied to any account using that rule. In the customer-managed model, the customer has a full copy of the rule, and executes the rule within his/her own account. These rules are maintained by the customer.

Q: How many rules can I create?

You can create up to 50 rules in your AWS account by default. Additionally, you can request an increase for the limit on the number of rules in your account by visiting the AWS Service Limits page.

Q: How are rules evaluated?

Any rule can be setup as a change-triggered rule or as a periodic rule. A change-triggered rule is executed when AWS Config records a configuration change for any of the resources specified. Additionally, one of the following must be specified:

  • Tag Key:(optional Value): A tag key:value implies any configuration changes recorded for resources with the specified tag key:value will trigger an evaluation of the rule.
  • Resource type(s): Any configuration changes recorded for any resource within the specified resource type(s) will trigger an evaluation the rule.
  • Resource ID: Any changes recorded to the resource specified by the resource type and resource ID will trigger an evaluation of the rule.

A periodic rule is triggered at a specified frequency. Available frequencies are 1hr, 3hr, 6hr, 12hr or 24hrs. A periodic rule has a full snapshot of current Configuration Items (CIs) for all resources available to the rule.

Q: What is an evaluation?

Evaluation of a rule determines whether a rule is compliant with a resource at a particular point in time. It is the result of evaluating a rule against the configuration of a resource. Config Rules will capture and store the result of each evaluation. This result will include the resource, rule, time of evaluation and a link to Configuration Item (CI) that caused non-compliance.

Q: What does compliance mean?

A resource is compliant if complies with all rules that apply to it. Otherwise it is noncompliant. Similarly, a rule is compliant if all resources evaluated by the rule comply with the rule. Otherwise it is noncompliant. In some cases, such as when inadequate permissions are available to the rule, an evaluation may not exist for the resource, leading to a state of insufficient data. This state is excluded from determining the compliance status of a resource or rule.

Q: What information does the Config Rules dashboard provide?

The Config Rules dashboard gives you an overview of resources tracked by AWS Config, and a summary of current compliance by resource and by rule. When you view compliance by resource, you can determine if any rule that applies to the resource is currently not compliant. You can view compliance by rule, which tells you if any resource under the purview of the rule is currently non-compliant. Using these summary views, you can dive deeper into the Config timeline view of resources, to determine which configuration parameters changed. Using this dashboard, you can start with an overview and drill into fine-grained views that give you full information about changes in compliance status, and which changes caused non-compliance.