Log groups and log streams in AWS - Practice Problems & Coding Challenges

Challenge - 5 Problems

🧠 Conceptual

intermediate

Understanding Log Group Retention

You create a CloudWatch Log Group with a retention period of 7 days. What happens to the log data after 7 days?

A The log data is moved to a new log stream after 7 days.

B The log data is archived indefinitely after 7 days.

C The log data is automatically deleted after 7 days.

D The log data remains until you manually delete the log group.

💡 Hint

Think about what retention means for data lifecycle.

Retention period defines how long logs are kept. After that, logs are deleted automatically.

❓ Architecture

intermediate

Log Stream Creation Behavior

Which statement best describes when a new log stream is created in a CloudWatch Log Group?

A A new log stream is created automatically for each unique source sending logs.

B You must manually create all log streams before sending logs.

C Log streams are created only when you enable log retention.

D Log streams are created only when you delete the log group.

💡 Hint

Consider how logs from different sources are organized.

CloudWatch creates a new log stream automatically for each unique source or resource sending logs to a log group.

❓ service_behavior

advanced

Log Stream Sequence Token Usage

You are sending log events to a CloudWatch Log Stream using the AWS SDK. What happens if you send a batch of log events with an incorrect sequence token?

A The log events overwrite previous events in the stream.

B The log events are accepted but stored out of order.

C The log stream is deleted automatically.

D The API call fails with an InvalidSequenceTokenException error.

💡 Hint

Think about how CloudWatch ensures log event order.

CloudWatch requires the correct sequence token to maintain order. An incorrect token causes an error.

❓ security

advanced

IAM Permissions for Log Group Access

Which IAM permission is required to allow a user to create a new log stream in an existing CloudWatch Log Group?

A logs:CreateLogStream

B logs:CreateLogGroup

C logs:PutLogEvents

D logs:DeleteLogStream

💡 Hint

Focus on the permission that allows creating streams, not sending logs.

The logs:CreateLogStream permission allows creating new log streams within a log group.

✅ Best Practice

expert

Optimizing Log Group Design for Multiple Applications

You manage logs for multiple applications in your AWS account. Which approach is best to organize CloudWatch Log Groups and Log Streams for clear separation and easy management?

A Create one log stream per application and multiple log groups per application instance.

B Create one log group per application and multiple log streams per application instance.

C Create one log group for all applications and one log stream per application.

D Create one log group and one log stream for all applications combined.

💡 Hint

Think about how to separate logs logically and manage retention easily.

Creating one log group per application allows setting retention and access controls per app. Multiple log streams per instance keep logs organized.