Master Health Tests

This Master health test checks that the number of file descriptors used does not rise above some percentage of the Master file descriptor limit. A failure of this health test may indicate a bug in either Hadoop or Cloudera Manager. Contact Cloudera support. This test can be configured using the File Descriptor Monitoring Thresholds Master monitoring setting.

Short Name: File Descriptors

This Master health test checks that the Master is not spending too much time performing Java garbage collection. It checks that no more than some percentage of recent time is spent performing Java garbage collection. A failure of this health test may indicate a capacity planning problem or misconfiguration of the Master. This test can be configured using the Garbage Collection Duration Thresholds and Garbage Collection Duration Monitoring Period Master monitoring settings.

Short Name: GC Duration

This is an HBase Master health test that checks that a client can connect to and get basic information from the Master in a reasonable amount of time. The test returns "Bad" health if the connection to or basic queries of the Master fail. The test returns "Concerning" health if the connection attempt or queries do not complete in a reasonable time. A failure of this health test may indicate that the Master is failing to satisfy basic client requests correctly or in a timely fashion. Check the status of the Master, and look in the Master logs for more details. This test can be enabled or disabled using the HBase Master Canary Health Test HBase Master monitoring setting.

Short Name: HBase Master Canary

This Master health test factors in the health of the host upon which the Master is running. A failure of this test means that the host running the Master is experiencing some problem. See that host's status page for more details.This test can be enabled or disabled using the Master Host Health Test Master monitoring setting.

Short Name: Host Health

This Master health test checks that the filesystem containing the log directory of this Master has sufficient free space. This test can be configured using the Log Directory Free Space Monitoring Absolute Thresholds and Log Directory Free Space Monitoring Percentage Thresholds Master monitoring settings.

Short Name: Log Directory Free Space

This Master health test checks that the Cloudera Manager Agent on the Master host is heart beating correctly and that the process associated with the Master role is in the state expected by Cloudera Manager. A failure of this health test may indicate a problem with the Master process, a lack of connectivity to the Cloudera Manager Agent on the Master host, or a problem with the Cloudera Manager Agent. This test can fail either because the Master has crashed or because the Master will not start or stop in a timely fashion. Check the Master logs for more details. If the test fails because of problems communicating with the Cloudera Manager Agent on the Master host, check the status of the Cloudera Manager Agent by running /etc/init.d/cloudera-scm-agent status on the Master host, or look in the Cloudera Manager Agent logs on the Master host for more details. This test can be enabled or disabled using the Master Process Health Test Master monitoring setting.

Short Name: Process Status

This Master health test checks that the Master has not recently exited unexpectedly. The test returns "Bad" health if the number of unexpected exits goes above a critical threshold. For example, if this test is configured with a critical threshold of 1, this test would return "Good" health if there have been no unexpected exits recently. If there has been 1 or more unexpected exits recently, this test would return "Bad" health. This test can be configured using the Unexpected Exits Thresholds and Unexpected Exits Monitoring Period Master monitoring settings.

Short Name: Unexpected Exits

This health test checks that the role's web server is responding quickly to requests by the Cloudera Manager Agent, and that the Cloudera Manager Agent can collect metrics from the web server. Failure of this health test may indicate a problem with the web server of the Master, a misconfiguration of the Master or a problem with the Cloudera Manager Agent. Consult the Cloudera Manager Agent logs and the logs of the Master for more detail. If the test's failure message indicates a communication problem, the Cloudera Manager Agent's HTTP requests to the Master's web server are failing or timing out. If the test's failure message indicates an unexpected response, the Master's web server responded to the Cloudera Manager Agent's request, but the response could not be interpreted for some reason. This test can be configured using the Web Metric Collection Master monitoring setting.

Short Name: Web Server Status