How to View Hadoop Logs
There are multiple ways to view logs in Hadoop. Some commonly used methods include:
- Hadoop log files: Each node in the Hadoop cluster generates log files that contain detailed information about job execution. You can SSH into the nodes in the Hadoop cluster and view their respective log files. By default, the log files are located in the ‘logs’ folder within the Hadoop installation directory.
- Hadoop Log Aggregation Tool: Hadoop offers tools for aggregating and analyzing log files within a cluster. For instance, the Hadoop Log Aggregation tool can consolidate log files from all nodes into one location, allowing for easy viewing and analysis using the Hadoop Log Viewing tool.
- Hadoop Web Interface: Hadoop offers a web interface that allows you to view the status and log information of jobs running. You can access the URL of the ResourceManager or JobTracker nodes in the Hadoop cluster through your browser, and then navigate to the respective job page to view the logs.
- Hadoop command-line tools allow users to view and analyze log files. For example, the command “hadoop fs” can be used to view log files in the Hadoop Distributed File System (HDFS), or the “yarn logs” command can be used to view job logs.
These methods can be chosen based on your needs. Depending on the specific issues you are facing, it may be necessary to combine the above methods to view and analyze Hadoop logs.
