Loki

Loki: Efficient, open-source logging system by Grafana. Collects, indexes, and queries logs for streamlined monitoring and troubleshooting. Highly scalable.

INTRODUCTION

For thorough logging, use the Loki data source by going to "Explore" in Grafana's navigation pane. This feature is critical for in-depth log analysis because it allows for query creation, visualization, and correlation of log data. It provides a comprehensive picture that aids in troubleshooting, monitoring, and system performance optimization.

COMMON USES OF LOKI

• The "Line Contains" action in Loki is used to search for a specific and exact string within logs, allowing for targeted and specialized log retrieval and analysis.

  • example - Regex can be used to match certain strings inside transaction data, providing a versatile and powerful approach for searching for patterns, extracting useful information, and detecting anomalies within transactional logs or records. This aids in data analysis, validation, and pattern detection, allowing for more efficient processing and decision-making.

  

  
• Specifically, the "Line Does Not Contain" operation in Loki filters log lines based on the absence of a specific string, allowing you to eliminate log entries that do not include the requested text. This aids in refining the search and concentrating on important log data.

  • example - Earlier, too many generate challenge failures were expected errors. So, filtered them using Line does not contain operation.

  

• Users can view a list of previously ran searches by using the query history function. It allows you to easily access and rerun prior queries without having to retype them, making it easier to revisit and analyze earlier log data searches or inquiries. This feature improves process efficiency and makes historical log analysis easier.

• Use Loki with Grafana to perform real-time network debugging with configurable logging. Create and iterate Loki queries, monitor live logs, and refine searches to observe network behavior and fix problems quickly for improved performance and dependability.

• Utilize Loki's time range functionality in Grafana to inspect logs from previous runs. Define the time window that will be used to precisely analyze historical logs, assisting in debugging, issue resolution, and performance optimization for earlier system executions.

• To run custom script queries, use the "Download logs" feature included in the inspector. This enables personalized log analysis, providing precise and detailed information based on your individual needs

• Loki queries can use regular expressions (regex) to do flexible and pattern-based log searches. Regex allows you to build complicated search patterns, allowing for versatile log filtering and extraction based on specific criteria, hence improving log analysis and troubleshooting skills.

  • example - This regex pattern will match the specific string "Not enough tokens to honor allocation" followed by a space, then one or more digits (represented by \d+), followed by a space, the less-than symbol <, and then one or more digits again.

    Not enough tokens to honor allocation \d+ < \d+ 

For more log queries refer Loki official doc - https://grafana.com/docs/loki/latest/query/log_queries/