Audit logging in Hadoop - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is audit logging in Hadoop?

Audit logging in Hadoop records all user actions and system events to track access and changes for security and compliance.

beginner

Which Hadoop component is primarily responsible for audit logging?

The NameNode is primarily responsible for audit logging because it manages file system metadata and records user access events.

intermediate

Where are Hadoop audit logs typically stored?

Audit logs are usually stored in log files on the NameNode server, often under the directory configured by the property 'dfs.namenode.audit.log.dir'.

intermediate

How can you enable audit logging in Hadoop?

Audit logging is enabled by default in Hadoop. You can configure its details in the 'hdfs-site.xml' file, such as log directory and log rolling policies.

beginner

Why is audit logging important in Hadoop environments?

Audit logging helps detect unauthorized access, troubleshoot issues, and meet compliance requirements by providing a detailed record of user and system actions.

What does Hadoop audit logging primarily track?

A User access and file system changes

B CPU and memory usage

C Network traffic

D Data replication status

Audit logging tracks user access and file system changes to monitor security and compliance.

Which Hadoop configuration file controls audit logging settings?

A core-site.xml

B hdfs-site.xml

C mapred-site.xml

D yarn-site.xml

Audit logging settings are configured in hdfs-site.xml.

Where are audit logs stored by default in Hadoop?

A On the NameNode server

B On the DataNode server

C In HDFS user directories

D In the ResourceManager logs

Audit logs are stored on the NameNode server where metadata is managed.

What is a key benefit of audit logging in Hadoop?

A Improves data compression

B Manages cluster resources

C Speeds up data processing

D Tracks unauthorized access

Audit logging helps track unauthorized access for security.

Which Hadoop component generates audit logs?

A ZooKeeper

B DataNode

C NameNode

D JobTracker

The NameNode generates audit logs as it manages file system metadata.

Explain what audit logging is in Hadoop and why it is important.

Think about how Hadoop keeps records of who did what and why that matters.

Describe how to find and configure audit logging settings in a Hadoop cluster.

Focus on the configuration file and the server responsible.

Practice

1. What is the main purpose of audit logging in Hadoop?

easy

A. To backup data automatically

B. To improve data processing speed

C. To compress files for storage

D. To track user actions for security and troubleshooting

Solution

1. Step 1: Understand audit logging function

   Audit logging records user actions like access and changes in Hadoop.

2. Step 2: Identify main goal

   This helps with security checks and troubleshooting issues.

3. Final Answer:

   To track user actions for security and troubleshooting -> Option D

4. Quick Check:

   Audit logging = Track user actions [OK]

Hint: Audit logs = user actions tracking for security [OK]

Common Mistakes:

• Confusing audit logging with data backup
• Thinking audit logs speed up processing
• Mixing audit logging with file compression

2. Which configuration property must be set to true to enable audit logging in Hadoop?

easy

A. hadoop.logging.audit.enabled

B. hadoop.security.audit.enable

C. hadoop.audit.logging.active

D. hadoop.security.authorization

Solution

1. Step 1: Identify correct property name

   The official property to enable audit logging is hadoop.security.audit.enable.

2. Step 2: Confirm value to enable

   Setting it to true activates audit logging features.

3. Final Answer:

   hadoop.security.audit.enable -> Option B

4. Quick Check:

   Enable audit logging = hadoop.security.audit.enable true [OK]

Hint: Enable audit with hadoop.security.audit.enable true [OK]

Common Mistakes:

• Using incorrect property names
• Setting property to false
• Confusing audit logging with general logging

3. Given the following audit log entry:

2024-06-01 10:15:30 INFO User: alice accessed /data/input/file1.txt

What does this log entry indicate?

medium

A. User alice modified the file /data/input/file1.txt

B. User alice deleted the file /data/input/file1.txt

C. User alice accessed the file /data/input/file1.txt

D. User alice created the file /data/input/file1.txt

Solution

1. Step 1: Read the log message carefully

   The log states "User: alice accessed /data/input/file1.txt" which means alice opened or read the file.

2. Step 2: Understand the action word

   "accessed" means viewing or reading, not modifying or deleting.

3. Final Answer:

   User alice accessed the file /data/input/file1.txt -> Option C

4. Quick Check:

   Access means read/view, not modify [OK]

Hint: Look for action verb in log entry to know user activity [OK]

Common Mistakes:

• Assuming access means modification
• Confusing access with deletion
• Ignoring the exact log message wording

4. You enabled audit logging by setting hadoop.security.authorization to true, but no audit logs are generated. What is the most likely cause?

medium

A. Audit logger classes are not configured properly

B. Hadoop service is not running

C. User permissions are too high

D. Audit logging is disabled by default

Solution

1. Step 1: Check audit logging prerequisites

   Besides enabling authorization, audit logger classes must be configured to capture logs.

2. Step 2: Identify missing configuration

   If audit logger classes are missing or misconfigured, no logs will appear despite enabling authorization.

3. Final Answer:

   Audit logger classes are not configured properly -> Option A

4. Quick Check:

   Enable + configure logger classes = audit logs [OK]

Hint: Enable plus configure logger classes to get audit logs [OK]

Common Mistakes:

• Assuming service not running causes no logs
• Thinking user permissions block audit logs
• Ignoring need to configure logger classes

5. You want to audit all user actions on Hadoop files and see who changed data and when. Which combination of steps is correct?

hard

A. Set hadoop.security.authorization=true and configure audit logger classes

B. Set hadoop.security.authorization=false and enable debug logging

C. Only configure audit logger classes without enabling authorization

D. Enable file system replication and audit logging

Solution

1. Step 1: Enable security authorization

   Setting hadoop.security.authorization=true activates audit logging capability.

2. Step 2: Configure audit logger classes

   These classes capture and record user actions in logs.

3. Final Answer:

   Set hadoop.security.authorization=true and configure audit logger classes -> Option A

4. Quick Check:

   Enable authorization + logger classes = full audit [OK]

Hint: Enable authorization and logger classes for full audit [OK]

Common Mistakes:

• Disabling authorization but expecting audit logs
• Relying on debug logging for audit
• Confusing replication with audit logging