When I run a mapping on the Blaze engine and try to view the grid task log, the Blaze Job Monitor does not fetch the full log.
The grid task log might be too large. The Blaze Job Monitor can only fetch up to 2 MB of an aggregated log. The first line of the log reports this information and provides the location of the full log on HDFS. Follow the link to HDFS and search for "aggregated logs for grid mapping." The link to the full log contains the grid task number.
The Blaze Job Monitor will not start.
Check the Hadoop environment logs to locate the issue. If you do not find an issue, stop the Grid Manager with the infacmd stopBlazeService command and run the mapping again.
The Monitoring URL is not displayed in the Properties view of the Administrator tool.
Locate the URL in the YARN log.
A Blaze Job Monitor that has been running for several days loses its connection to the Application Timeline Server on the Hortonworks cluster.
The Blaze engine requires a running Application Timeline Server on the cluster. When the Blaze engine starts a mapping run, the Blaze Job Monitor checks the state of the Application Timeline Server. The Grid Manager will start it if it is not running. When the connection to the Application Timeline Server is lost, the Blaze engine attempts to reconnect to it. If the Application Timeline Server stops during a Blaze mapping run, you can restart it by restarting the Grid Manager.
When the Application Timeline Server is configured to run on the cluster by default, the cluster administrator must manually restart it on the cluster.