Using log correlators to detect relationships in log data
Summarize
Summary of Using Log Correlators to Detect Relationships in Log Data
Log correlators are essential tools in IT Operations Management that help identify correlations between alerts by analyzing log data. They can detect simultaneous occurrences of specific log elements, such as interface IDs across different application services, thereby enhancing incident response and troubleshooting capabilities.
Show less
Key Features
- Types of Log Correlators: There are two main types:
- Free Text Correlators: Analyze the text within log messages to identify correlations. They are ideal for terms not structured as log properties, such as "policy-id" or application names unique to your environment.
- Log Property Correlators: Focus on the metadata portion of log lines. They help detect relationships based on specific attributes like application service names or interface IDs.
- Log Source Specification: Users can choose to analyze log data from all sources, new sources only, or specified sources based on their needs.
- Custom Correlators: The base system includes predefined correlators, but customers can also define their own to better fit their unique operational context.
Key Outcomes
By effectively using log correlators, organizations can:
- Detect related alerts, improving troubleshooting efficiency.
- Quickly correlate incidents across different systems and applications, leading to faster resolution times.
- Gain insights into operational relationships, enhancing overall IT operational health.
For detailed instructions on adding and managing log correlators, refer to the guidelines provided in the relevant documentation.
Log correlators are keys or values in log data that detect correlations between alerts. For example, a log correlator could detect when the interface ID of a particular network device occurs simultaneously in multiple warnings across different application services.
Types of log correlators
Most log lines include a metadata portion plus a message portion. Some log lines, however, include only message text with metadata included in the text.
The two types of log correlators, free text correlators and log property correlators, analyze the different portions of each log to identify relationships between log data from multiple log sources.
- Free text correlators
Free text correlators analyze the text within the log message portion of log lines that are associated with an anomaly. The system uses free text correlators to identify correlations between alerts. You use free text correlators to add a term that you expect to appear within log messages. A good choice is a term that is not structured and would not otherwise be extracted as a log property. For example, “policy-id” or “ thread-id”.
You also typically add free text correlators for the names of systems, applications, and services that are unique to your environment. Because such a value can be referred to by multiple sources, layers, middleware, or databases, the free text correlator can be an effective detector of correlated alerts. For example, if your organization's service is called TeaTime, then you might add "teatime" as a free text correlator. The correlator would identify alerts that are related because they were generated for resources that support the TeaTime service, such as a database lock or a connection failure between TeaTime components.
- Log property correlators
Log property correlators analyze the metadata portion of log lines. For example, the correlator can analyze the name of an application service, the interface ID of a network device, or the request ID of a web-facing component. A log property correlator could flag a correlation when the interface ID of a network device simultaneously occurs in multiple warnings in different log sources. Log property correlators are specific to the business context of your environment.
Specifying the log sources for a log correlator
- Only new sources: The system applies the log correlator only to log lines from log sources that were created after this log correlator is activated.
- All sources: The system applies the log correlator to log lines from all log sources.
- Specified source: For a log correlator, the system analyzes only log lines from the log source that you specify.
For instructions for specifying the set of log sources, see Add a log correlator to identify relationships in logs.