Cloud Custodian for Policies Management: A Comprehensive Guide 

There is increasing complexity in the cloud environment today which calls for the need for effective management of its cloud resources and realization of compliance to policies. Cloud Custodian provides an open-source tool that has a framework and allows one to formulate and implement available solutions to the problem. Further in this article, we will describe how Cloud Custodian facilitates rather remarkably the management of policies, its features and use case, and the policies that should be followed when using it. 

What is Cloud Custodian? 

A cloud resource policy management tool named Cloud Custodian was created by Capital One’s employees and offers its users the ability to manage cloud resource policies in different cloud vendors, including AWS, Azure, and GCP. The main objective of Cloud Custodian is to facilitate the use of these policies in managing cloud resources determined by security, compliance, cost management, and resource management policies.

Cloud Custodian is an open-source cloud management tool hosted on GitHub, designed to facilitate governance and compliance across multi-cloud environments, including cloud custodian aws, cloud custodian azure, cloud custodian gcp, and cloud custodian kubernetes. It operates on a modular architecture, referred to as cloud custodian architecture, where users define resource management policies in YAML, allowing for automated tasks such as identifying non-compliant resources, optimizing costs by managing unused instances, and enforcing security best practices.

Additionally, cloud custodian terraform integrates with Terraform to enhance Infrastructure as Code (IaC) practices, ensuring governance from the provisioning stage. With a vibrant community contributing to its development and extensive cloud custodian training resources available, Cloud Custodian empowers organizations to maintain visibility and control over their cloud infrastructures effectively while enhancing security and compliance.

Key Features of Cloud Custodian

Policy as Code

With Cloud Custodian, one can write policies in a single easy to read and navigate YAML configuration file. This allows for easy versioning and distribution of policies amongst team members.

Multi-Cloud Support

No matter whether you are in the AWS or GCP territory, all the cloud resources management can be done under the umbrella of Cloud Custodian.

Automation

Cloud Custodian can also automate some mundane operational tasks, such as resource clean-ups, compliance tagging, and security control enforcement.

Advanced Filters and Actions

Users can enhance their selection criteria & actions regarding a specific resource for improved performance and effectiveness

Advanced Features of Cloud Custodian 

1. Custom Actions

Cloud custodian allows extending events by creating actions, and these are conditional with the use of certain triggers. For e.g. a company may choose to implement an action that posts messages on the slack channel after some certain limitations in resources have been exhausted. 

2. Event-Driven Automation

The cloud custodian solution can be configured and integrated with AWS Lambda or Azure functions for the purpose of cloud event management. This event-based strategy allows the implementation of policies in real-time whenever a change occurs within the cloud. 

3. Multi-Account Management

In an instance where an organization has several cloud account structures cloud custodian implements management across several accounts. For e.g. it is possible to define policies that enable multiple accounts to host cloud resources and provide a view of all the accounts in a single location. 

4. Resource Metrics

The cloud custodian employs resource metrics for policies that focus on cost optimization. Many other policies can also be implemented to reduce the number of underutilized overprovisioned instances over time. 

Why Use Cloud Custodian for Policy Management? 

1. Protection Elevated to New Heights: Implementing security policies with Cloud Custodian enables organizations to identify and mitigate the risks of wrongly configured elements.
   

2. Reducing expenditure on cloud resources: Organizations can minimize wasteful expenditure on cloud services because they can streamline the process of identifying which resources are not being used and even switching them off.
   

3. Regulatory Compliance: By functioning as a controlled checking device among the cloud resources, Cloud Custodian helps to eliminate the risk of chance regulatory violations on cloud-based systems.
   

4. Efficiency: Automating such practices through an application eases the workload on the IT departments, allowing them to focus on more important issues that are aimed at growing the business.

   
   

   

Fig 2: Multi-Account Security Governance as Code with Cloud Custodian on AWS

Getting Started with Cloud Custodian 

Prerequisites 

Before getting into details of Cloud Custodian, ascertain that the following are available:

• Basic Knowledge of Cloud Services: In-depth understanding of the cloud service provider in use and its offerings.  

• Python: Since Cloud Custodian is purely a Python application, one must install Python on the system.  

• Cloud Resources: A person must possess the required credentials and permissions to use cloud account resources. 

Installation 

To install Cloud Custodian, you can use pip, the Python package manager. Open your terminal and run: 

pip install c7n 

This command will install the Cloud Custodian package along with its dependencies. 

Configuration 

1. Set Up Credentials: For AWS, configure your AWS credentials using the AWS CLI: 

aws configure 

For Azure and GCP, refer to the respective cloud provider's documentation to set up credentials. 

2. Create a Policy File: Define your first policy in a YAML file. Here’s an example that identifies EC2 instances that are not tagged: 

3. Run the Policy: Execute the policy using the following command: 

custodian run -s . untagged-ec2-instances.yml 

This command runs the policy and stores the results in the specified directory. 

Common Use Cases for Cloud Custodian 

1. Resource Cleanup: On-demand destruction of resources that are no longer in use permanently, such as EC2 instances or load balancers and mower costs. 

2. Security Auditing: Locate and fix risks in security configurations, e.g., open security groups or overly permissive IAM policies. 

3. Compliance Monitoring refers to the periodic evaluation of the available resources for the measures that are in place within the organization or any other applicable legislation, such as GDPR or HIPAA. 

4. Tagging Enforcement: Ensure that every cloud asset is properly tagged for the appropriate cost management and control measures. 

5. Resource Modification: Change current resources by given conditions e.g. when usage of instance types changes, they may differ. 

Case Studies on Cloud Custodian for Policies Management

Case Study 1 - A Financial Services Provider 

This is a case where a financial services provider needed to better manage its cloud resources and remain compliant with the very stringent existing regulations. They decided to apply the Cloud Custodian to manage issues related to resource tagging, configuring security groups, and controlling costs. 

Results: 

• Increased Compliance: The first three months saw the firm decrease the instances of misconfigured resources by 60%. 

• Cost Efficiency: The firm reduced its monthly costs by approximately 25% by using the system to automatically shut down dead resources.  

Case Study 2 - E-Commerce Business 

As the popularity of an online shopping site skyrocketed, the use of cloud resources increased correspondingly and very rapidly. They also used Cloud Custodian to track policies for untagged resources and to configure S3 buckets. 

Results:  

Improved Resource Awareness

The firm’s resource tagging compliance improved from 30% to 85% in language months

Improved Security Posture

Reduced security concern was realized after putting in place policies to oversee S3 buckets

Case Study 3 - A Health Care Service Provider 

A health service provider was under regulatory pressure, such as HIPAA, and was not supposed to expose any sensitive data on the cloud. Cloud Custodian implemented a system responsible for geographic access control, Eliminating orbital storage locations without encryption available for product storage. 

Results: 

• Policy Adherence: The user could comply 100% with the HIPAA data protection policies on encryption. 

• Instead of relying on human labor to report compliance proportions, Cloud Custodian allowed these proportions to be reported almost automatically. 

Future Scope of Cloud Custodian 

1. Leveraging AI and ML: As more businesses embrace the benefits of AI and ML, Cloud Custodian's resource optimization capabilities can be improved by incorporating predictive resource usage trends. 

2. Increased Multi/Hybrid Cloud Adoption: Improvements in future releases may encompass additional cloud providers and/or other cloud services global policy management, providing users with better policy management. 

3. Improved User Experience: Considering the fact that Cloud Custodian is mostly a CLI, there are chances that users may want to have a policy management GUI for more convenient interaction with the application. 

4. Continuous Development from the Community: The future improvement prospects of Cloud Custodian bear in mind that this is an open-source project meaning there will be continuous enhancements. 

5. Automation of Security Checks: More integration with CI/CD tools and DevOps practices will enable organizations to practice security and compliance even earlier in the development life cycle.