Tutorial / Cram Notes
AWS Cost Explorer is a tool that allows you to visualize your AWS spending and usage patterns. It can be used to identify unused resources by analyzing the data for any anomalies or low-activity services. For example, you might find that certain EC2 instances are running 24/7 but have very low utilization metrics, indicating that they may be downsized or removed.
AWS Trusted Advisor
Trusted Advisor is an application that inspects your AWS environment and provides real-time guidance to help you provision your resources following AWS best practices. Under the Cost Optimization category, Trusted Advisor checks include “Low Utilization Amazon EC2 Instances” and “Underutilized Amazon EBS Volumes”. It provides detailed reports on resources that are potentially idle or unused.
Amazon CloudWatch
CloudWatch is a monitoring service that can be configured to track performance and operational health of AWS services and applications. For identifying unused resources, you can set CloudWatch to alert you when metrics fall below a certain threshold, such as low NetworkIn and NetworkOut for EC2 instances, indicating that the instance might be idle.
AWS Config
AWS Config is a service that enables you to assess, audit, and evaluate the configurations of your AWS resources. AWS Config can track changes over time and can be utilized to identify resources that are not in use or not required by logging and analyzing configuration histories.
AWS Resource Groups and Tagging
Resource Groups and Tagging allow you to create a structured taxonomy for your resources. By tagging resources with details such as project name, environment, or owner, you can quickly assess which resources might no longer be in use. You can use the Tag Editor to search for resources without specific tags and investigate whether they are necessary.
Automation with AWS Lambda
AWS Lambda can be used to automate the process of identifying and taking action on unused resources. For example, you could write a Lambda function that, when triggered on a schedule, will check for EC2 instances with CPU utilization under a certain percentage over a given period and then stop or terminate those instances.
import boto3
def lambda_handler(event, context):
ec2_client = boto3.client(‘ec2’)
instances = ec2_client.describe_instances()
for reservation in instances[‘Reservations’]:
for instance in reservation[‘Instances’]:
instance_id = instance[‘InstanceId’]
# Assume we’ve collected CloudWatch metrics separately
# and determined the instance is underutilized
if is_instance_underutilized(instance_id):
ec2_client.stop_instances(InstanceIds=[instance_id])
print(f’Stopped underutilized instance: {instance_id}’)
def is_instance_underutilized(instance_id):
# Logic to determine if instance is underutilized
pass
Cost and Usage Report
The AWS Cost and Usage Report contains the most comprehensive set of AWS cost and usage data available, including additional metadata about AWS services, pricing, and reservations. By analyzing these comprehensive reports, you may discover resources generating costs without corresponding usage.
AWS Budgets
AWS Budgets can alert you when your costs or usage exceed predefined thresholds. This is useful not only for managing costs but also for detecting anomalies that may indicate unused resources.
Comparing Strategies:
| Strategy | Use Case | Advantage |
|---|---|---|
| AWS Cost Explorer | Visual trend analysis | Easy visualization of spending patterns |
| AWS Trusted Advisor | Best practices adherence | Real-time recommendations |
| Amazon CloudWatch | Performance monitoring | Customizable metrics and alerts |
| AWS Config | Configuration tracking | Resource inventory and change tracking |
| AWS Resource Groups | Organizational structure | Grouped management of resources |
| AWS Lambda Automation | Proactive resource management | Custom automation of resource optimization |
| Cost and Usage Report | Detailed cost analysis | Deep dive into cost data |
| AWS Budgets | Cost control | Proactive budgeting and cost alerts |
In preparing for the AWS Certified Solutions Architect – Professional exam, understanding how to implement and leverage these tools is essential. Scenario-based questions may test your ability to identify the most cost-effective solution to a given problem, which often involves recognizing and eliminating wasted spend due to unused resources. By mastering the use of these AWS tools, you can design not only cost-effective but also highly optimized and scalable systems on AWS.
Practice Test with Explanation
True or False: AWS Trusted Advisor does not provide any insights on unused resources.
- Answer: False
Explanation: AWS Trusted Advisor provides insights into your AWS environment, including recommendations for unused resources and cost optimization.
Which AWS service can be used to visualize and understand AWS spend, and pinpoint underutilized resources?
- A. AWS Budgets
- B. AWS Cost Explorer
- C. AWS Trusted Advisor
- D. AWS CloudTrail
Answer: B. AWS Cost Explorer
Explanation: AWS Cost Explorer allows users to visualize and manage AWS spending, as well as identify underutilized resources.
True or False: Amazon EC2 Reserved Instances that are not being fully utilized can result in unnecessary costs.
- Answer: True
Explanation: If Reserved Instances are not utilized, the cost benefits are not realized and they can lead to unnecessary costs.
Which of the following AWS services identifies unattached Elastic IP addresses?
- A. AWS CloudTrail
- B. AWS Trusted Advisor
- C. AWS Config
- D. Amazon CloudWatch
Answer: B. AWS Trusted Advisor
Explanation: AWS Trusted Advisor detects unattached Elastic IP addresses which can incur costs.
True or False: AWS Config cannot track changes to AWS resources, making it ineffective at identifying unused resources.
- Answer: False
Explanation: AWS Config can track changes to the AWS resources’ configurations and can be used to identify unused or underutilized resources.
Multiple Select Question: Which of the following tools can help in identifying idle Amazon RDS instances? (Select TWO)
- A. AWS Trusted Advisor
- B. AWS Cost Explorer
- C. AWS CloudTrail
- D. AWS Config
Answer: A. AWS Trusted Advisor and B. AWS Cost Explorer
Explanation: AWS Trusted Advisor provides recommendations on cost optimization, including identifying idle RDS instances. AWS Cost Explorer can also help in analyzing usage patterns to identify underutilized RDS instances.
AWS Lambda functions that are not executed for a long period indicate which of the following?
- A. They are optimized and cost-effective
- B. They are likely to be used but reserved for peak times
- C. They may be unused or redundant
- D. They are auto-scaled by AWS
Answer: C. They may be unused or redundant
Explanation: If AWS Lambda functions are not executed over an extended period, they may be unused or redundant, and their existence might not be justified.
Which AWS feature allows you to monitor and automatically terminate underutilized EC2 instances?
- A. AWS Auto Scaling
- B. AWS Instance Scheduler
- C. EC2 Auto Recovery
- D. AWS CloudFormation
Answer: B. AWS Instance Scheduler
Explanation: AWS Instance Scheduler can help in stopping or terminating underutilized EC2 instances according to schedules, thereby saving costs.
True or False: Deleting unused Amazon EBS volumes does not result in cost savings because they are free when not attached to an EC2 instance.
- Answer: False
Explanation: Unused Amazon EBS volumes do incur costs even when they are not attached to EC2 instances, and deleting them can result in cost savings.
Which of the following AWS services can alert you to increased spend or cost anomalies, potentially indicating underutilized resources?
- A. AWS Cost and Usage Report
- B. AWS Cost Anomaly Detection
- C. AWS Simple Monthly Calculator
- D. AWS CloudFormation
Answer: B. AWS Cost Anomaly Detection
Explanation: AWS Cost Anomaly Detection service can alert you to unexpected changes in spend, which may uncover underutilized resources.
True or False: AWS Elastic Beanstalk environments that are not active can be left running without incurring any costs.
- Answer: False
Explanation: Even if AWS Elastic Beanstalk environments are not active, they can still incur costs due to the underlying resources, so they should be terminated if not in use.
In order to track down and identify underutilized Amazon DynamoDB tables, you should look at the:
- A. Consumed read and write capacity units
- B. Number of items in the table
- C. Size of the table on disk
- D. Frequency of AWS Lambda triggers
Answer: A. Consumed read and write capacity units
Explanation: Monitoring the consumed read and write capacity units can help determine the utilization level of a DynamoDB table. If capacity units are consistently low, the table may be underutilized.
Interview Questions
What AWS service could help you identify underutilized or unused EC2 instances across your environment?
AWS Cost Explorer helps identify underutilized or unused EC2 instances by providing a visualization of your AWS spending and usage patterns. It can show usage data that may indicate idle or low-utilization instances which can be downsized or terminated to save costs.
How can AWS Trusted Advisor assist you in identifying unused or underutilized resources?
AWS Trusted Advisor provides real-time guidance to help you provision your resources following AWS best practices. It has checks for identifying underutilized resources, such as idle load balancers, underutilized EBS volumes, or EC2 instances.
Can Amazon CloudWatch be used to detect unused AWS resources? If so, how?
Yes, Amazon CloudWatch can be used to monitor metrics and set alarms for AWS resources which can help identify unused resources by setting thresholds that, when not surpassed, may indicate a resource isn’t being actively used, such as low network throughput on an EC2 instance.
Explain how AWS Config can be used to identify non-compliant resources that are potentially unused or unnecessary.
AWS Config allows you to assess, audit, and evaluate the configurations of your AWS resources. By defining custom rules or using the required tags for resources, AWS Config can help identify resources that are non-compliant because they’re not in use or needed, indicating potential candidates for termination.
What is the role of AWS Resource Groups and Tag Editor in managing and identifying unused AWS resources?
AWS Resource Groups and Tag Editor facilitate the organization and management of resources by categorizing them using tags. By grouping and tagging resources, you can easily identify which ones are underutilized or not used at all—enabling a systematic approach to clean up unnecessary resources.
Describe the process of conducting a cost optimization assessment in AWS to find unused resources.
A cost optimization assessment involves using tools like AWS Cost Explorer, AWS Budgets, and AWS Trusted Advisor to analyze your AWS spending and usage. The assessment looks for cost-saving opportunities such as subscribing to Reserved Instances or identifying unused resources that can be shut down or rightsized.
How can you use AWS Budgets to help manage costs and identify when resources might be unused?
AWS Budgets lets you set custom cost and usage budgets that alert you when your spending exceeds your planned budget. Budgets can also be set for specific services or tags, enabling you to notice if certain resources have lower-than-expected costs, which may signify they are unused or underutilized.
What steps would you take to decommission identified unused resources in AWS while ensuring no dependencies are disrupted?
First, I would conduct an audit to confirm that these resources are indeed unused and identify any dependencies. Next, I would update any relevant documentation and notify stakeholders. Then, I would create snapshots or backups if necessary before safely decommissioning the resources, following the infrastructure as code principles for reversibility if needed.
Can you describe how the AWS Well-Architected Tool can be instrumental in identifying cost optimization opportunities related to unused AWS resources?
The AWS Well-Architected Tool helps you review the state of your workloads and compare them to the latest AWS best practices. The cost optimization pillar of the tool includes checks for resource utilization and efficiency, leading to identifying unused or underutilized resources that can be eliminated or downsized.
Explain how using AWS Auto Scaling can indirectly help in identifying unused resources.
AWS Auto Scaling monitors your applications and automatically adjusts capacity to maintain steady, predictable performance at the lowest possible cost. By reviewing the scaling activities, you can identify patterns or trends that show certain instances may not be needed during specific times, indicating potentially unused resources.
How can AWS Lambda be used to automate the process of identifying and flagging unused resources?
AWS Lambda can be employed to run custom scripts triggered on a scheduled basis (using Amazon CloudWatch Events) that check for metrics indicating unused resources—such as low network activity, zero database connections, or idle compute instances—and then flag them for review or termination.
In what way does AWS IAM play a part in managing unused resources, especially in terms of security and compliance?
AWS IAM allows granular control over who can access and manage AWS resources. It plays a part in managing unused resources by ensuring only authorized users can terminate or modify them, which is critical when cleaning up unused resources to prevent accidental deletion of necessary assets and maintain compliance with security policies.
This blog post about using AWS solutions to identify unused resources is incredibly useful, especially while preparing for the SAP-C02 exam. Thanks!
Can anyone share their experience using AWS Trusted Advisor for finding unused resources?
Thanks for the insightful post!
Anyone used AWS CloudFormation StackSets for resource management?
This was very helpful, appreciate it!
I found AWS Cost Explorer effective for identifying unused resources. Any thoughts?
Great blog post, very useful!
Using AWS Config as a part of resource management strategy is underestimated but highly effective. Anyone using it?