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Splunk Parsing & Log Analysis Lab (TryHackMe – FixIt)
This lab documents hands-on Splunk log parsing and analysis tasks completed as part of the
TryHackMe “FixIt” room.
The purpose of this lab is to demonstrate practical understanding of SIEM data ingestion and parsing, including identifying incorrect event breaking, fixing parsing issues, and extracting meaningful fields required for security investigations.
Lab Environment
Platform
Operating System
- Linux-based virtual machine
Tools
Log Source
- Network log dataset provided by the lab environment
Objectives
This lab demonstrates the ability to:
- Identify incorrect log ingestion behaviour in Splunk;
- Fix event breaking issues at ingestion time;
- Configure field extraction for security-relevant attributes;
- Validate parsing improvements through analysis;
- Perform log-based investigation and research.
Lab Tasks and Implementation
Step 1. Launch Splunk and Identify Incorrect Event Breaking
- Launched Splunk Enterprise on the Linux virtual machine;
- Reviewed ingested network logs in the Search interface;
- Identified that Splunk was breaking events incorrectly;
- Observed that single log entries were split into two events.
This issue prevented proper analysis and confirmed the need for ingestion-time parsing fixes.

- Created a custom stanza in
props.conf to control how Splunk breaks events;
- Ensured each log entry would be indexed as a separate event.
Correct event breaking is critical for accurate timestamping, searching, and investigation.

- Created a regular expression-based extraction in
transforms.conf to extract key fields required for analysis, such as user identifiers, IP addresses, and domains;
- Prepared Splunk to extract structured fields from raw log events.

- Updated the existing
props.conf configuration;
- Linked the previously created transformation to the relevant sourcetype;
- Ensured field extraction would be applied during ingestion.
After this update, Splunk was able to correctly process and enrich incoming events.

- Defined extracted fields in
fields.conf;
- Ensured fields were available for searching and reporting;
- Applied best practices to avoid unnecessary index-time overhead.

- Verified that additional fields were correctly extracted;
- Ensured fields could be used for filtering and aggregation.
This validation confirmed that parsing issues had been fully resolved.

Step 7. Research and Investigation
- Analysed parsed log data using extracted fields;
- Performed research based on log contents;
- Answered all investigation questions provided by the lab.

Result
- Log events were correctly separated;
- Required fields were successfully extracted;
- Log data became suitable for investigation and analysis;
- All lab questions were answered based on parsed data.
Key Skills Demonstrated
- Splunk log parsing and troubleshooting;
- Event breaking configuration;
- Field extraction and validation;
- SIEM data quality improvement;
- Log-based security investigation.
Disclaimer
This lab was completed in a non-production, simulated, and isolated environment.
No real user data, credentials, or sensitive information were used.