The most surprising thing about Dynatrace Log Monitoring is that it doesn’t just collect logs; it actively understands them, transforming raw text into actionable insights without manual parsing rules for most common formats.
Let’s see this in action. Imagine you have a Java application generating logs.
Here’s a snippet of a typical log file:
2023-10-27 10:30:01 INFO [http-nio-8080-exec-1] com.example.MyApp - User 'alice' logged in successfully.
2023-10-27 10:30:05 ERROR [http-nio-8080-exec-2] com.example.MyApp - Database connection failed: java.sql.SQLException: Connection refused (Connection refused)
2023-10-27 10:30:10 WARN [http-nio-8080-exec-3] com.example.MyApp - Cache miss for resource: /api/v1/data
Once Dynatrace OneAgent is deployed and configured for log monitoring, it automatically detects these log files (or you can explicitly tell it where to look). You don’t need to write Grok patterns or regular expressions for standard JSON, log4j, or plain text formats. Dynatrace’s AI, known as Davis®, analyzes the log content, automatically extracts fields like timestamp, level, thread, logger, and the message.
In the Dynatrace UI, you’d navigate to "Logs" and see something like this, not just a wall of text:
| Timestamp | Level | Thread | Logger | Message | Host | Process Group |
|---|---|---|---|---|---|---|
| 2023-10-27 10:30:01 | INFO | http-nio-8080-exec-1 | com.example.MyApp | User 'alice' logged in successfully. | my-app-host | My Java App |
| 2023-10-27 10:30:05 | ERROR | http-nio-8080-exec-2 | com.example.MyApp | Database connection failed: java.sql.SQLException: Connection refused (Connection refused) | my-app-host | My Java App |
| 2023-10-27 10:30:10 | WARN | http-nio-8080-exec-3 | com.example.MyApp | Cache miss for resource: /api/v1/data | my-app-host | My Java App |
This structured data allows for powerful filtering and analysis. You can easily search for all ERROR level logs, filter by a specific User, or even search for logs containing java.sql.SQLException.
The Problem It Solves: Traditionally, log management involved setting up separate log shippers (like Filebeat, Fluentd), a log aggregation system (like Elasticsearch, Splunk), and then spending significant time defining parsing rules to extract meaningful data. This was time-consuming, brittle, and often missed crucial context. Dynatrace Log Monitoring integrates log data directly into its observability platform, correlating logs with traces, metrics, and topology. This means an error log message can be directly linked to the specific transaction that failed, the host it ran on, and the services it interacted with, providing instant root-cause analysis.
How it Works Internally: The Dynatrace OneAgent, running on your hosts, monitors specified log files. It uses a combination of intelligent pattern recognition (for common formats) and its AI engine to parse incoming log lines. For unstructured or custom formats, you can define custom log parsers using a user-friendly interface within Dynatrace, which then generates the necessary parsing logic on the agent. The parsed log records, enriched with context from the OneAgent (like host, process group, and even trace ID if available), are then sent to the Dynatrace backend. Here, Davis® further analyzes these logs, identifying anomalies, errors, and trends, and making them searchable and correlatable with other observability data.
Levers You Control:
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Log Source Configuration:
- Log Files: You specify the exact paths to log files or directories. Example:
/var/log/myapp/*.logor/opt/tomcat/logs/catalina.out. - Log Types: Dynatrace automatically detects common formats (JSON, Apache, Nginx, log4j, etc.). For custom formats, you’ll define parsing rules.
- Log Content Filtering: You can define rules to include or exclude specific log lines based on content, reducing noise and focusing on what matters. For instance, you might exclude all lines containing
"DEBUG"to save on storage and processing.
- Log Files: You specify the exact paths to log files or directories. Example:
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Log Processing and Parsing:
- Automatic Parsing: For supported formats, Dynatrace handles it.
- Custom Parsers: When automatic parsing fails, you can create custom parsers. This involves defining a name, selecting a parsing technology (e.g., Regex, JSONPath, Grok), and providing the pattern. For example, a custom regex parser for a peculiar format might look like:
^(\d{4}-\d{2}-\d{2} \d{2}:\d{2}:\d{2}) \[(.+)\] (.+?): (.*)$to extract timestamp, level, thread, and message. - Field Extraction: Even with automatic parsing, you can add custom field extractions to pull out specific pieces of information from the message payload that Davis® can then leverage.
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Ingestion and Retention:
- Ingestion Rate: Dynatrace has limits, but you can often adjust the ingestion rate or filtering to manage costs and performance.
- Retention Periods: Configure how long log data is stored in Dynatrace, balancing cost with the need for historical analysis.
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Alerting and Analysis:
- Log Monitoring Alerts: Set up alerts based on log content (e.g., "alert me if I see more than 5 ERROR logs in 5 minutes") or specific patterns.
- Log Viewer and Querying: Use the powerful log viewer with its query language to slice and dice your log data.
The real magic happens when Dynatrace automatically correlates a specific log entry, like a NullPointerException in your application logs, directly to the distributed trace of the failing request. This means you don’t just see the error; you see the exact sequence of service calls, timings, and parameters that led to that error, all within a single pane of glass.
Once you’ve mastered ingesting and analyzing your application logs, the next logical step is to leverage Dynatrace’s AI for anomaly detection on these logs, allowing you to proactively identify issues before they impact users.