Impala Daemon Health Tests

This Impala Daemon health test checks that the number of file descriptors used does not rise above some percentage of the Impala Daemon 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 Impala Daemon monitoring setting.

Short Name: File Descriptors

This Impala Daemon health test checks that the filesystem containing the heap dump directory of this Impala Daemon has sufficient free space. This test can be configured using the Heap Dump Directory Free Space Monitoring Absolute Thresholds and Heap Dump Directory Free Space Monitoring Percentage Thresholds Impala Daemon monitoring settings.

Short Name: Heap Dump Directory Free Space

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

Short Name: Host Health

This is an Impala Daemon health test that checks if the Impala Daemon is ready to process queries. This check usually fails if the YARN Node Manager is not available. If the YARN Node Manager goes offline, no resources can be acquired and new queries cannot be run. This test can be configured using the Impala Daemon Ready Status Health Check and Impala Daemon Ready Status Startup Tolerance impalad monitoring settings.

Short Name: Impala Daemon Ready Check

This is a Impala Daemon health test that checks that the filesystem containing the Impala Daemon Scratch Directories of this Impala Daemon has sufficient free space. See the Impala Daemon Scratch Directories description on the Impala Daemon configuration page for more information on this directory type. This test can be configured using the Impala Daemon Scratch Directories Free Space Monitoring Absolute Thresholds and Impala Daemon Scratch Directories Free Space Monitoring Percentage Thresholds Impala Daemon monitoring settings.

Short Name: Impala Daemon Scratch Directories Free Space

This Impala Daemon health test checks that the filesystem containing the log directory of this Impala Daemon 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 Impala Daemon monitoring settings.

Short Name: Log Directory Free Space

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

Short Name: Process Status

This Impala Daemon health test checks that the size of the resident set does not rise above a configured threshold value. A failure of this health test may indicates that the Impala Daemon process is consuming more memory than expected. It is possible that that unexpected memory consumption may lead to swapping and decreased performance for processes running on the same host as this Impala Daemon. Increased Impala Daemon memory consumption may be caused by an increased workload on the Impala service, or by a bug in the Impala Daemon software. To avoid failures of this health test, free up additional memory for this Impala Daemon process and increase the Resident Set Size Thresholds monitoring setting. This test can be configured using the Resident Set Size Thresholds Impala Daemon monitoring setting.

Short Name: Resident Set Size

This is an Impala Daemon health test that checks whether the StateStore considers the Impala Daemon alive. A failure of this health test may indicate that the Impala Daemon is having trouble communicating with the StateStore. Look in the Impala Daemon logs for more details. This test may return an unknown result if the Service Monitor is not able to communicate with the StateStore web server. Check the status of the StateStore web server and the Service Monitor logs if this test is returning an unknown result. This test can be enabled or disabled using the Impala Daemon Connectivity Health Test Impala Daemon monitoring setting. The Impala Daemon Connectivity Tolerance at Startup Impala Daemon monitoring setting and the Health Check Startup Tolerance StateStore monitoring setting can be used to control the test's tolerance windows around Impala Daemon and StateStore restarts respectively.

Short Name: StateStore Connectivity

This Impala Daemon health test checks the amount of swap memory in use by the role. A failure of this health test may indicate that your machine is overloaded. This test can be configured using the Process Swap Memory Thresholds monitoring settings.

Short Name: Swap Memory Usage

This Impala Daemon health test checks that the Impala Daemon has not recently exited unexpectedly. The test returns "Bad" health if the number of unexpected exits exceeds a critical threshold. For example, if this test is configured with a critical threshold of 1, this test returns "Good" health if there have been no unexpected exits recently. If 1 or more unexpected exits occured recently, this test returns "Bad" health. The test also indicates whether any of the exits were caused by an OutOfMemory error if the Cloudera Manager Kill When Out of Memory monitoring setting is enabled. This test can be configured using the Unexpected Exits Thresholds and Unexpected Exits Monitoring Period Impala Daemon 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 Impala Daemon, a misconfiguration of the Impala Daemon, or a problem with the Cloudera Manager Agent. Consult the Cloudera Manager Agent logs and the logs of the Impala Daemon for more detail. If the test failure message indicates a communication problem, the Cloudera Manager Agent's HTTP requests to the Impala Daemon's web server are failing or timing out. If the test's failure message indicates an unexpected response, the Impala Daemon'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 Impala Daemon monitoring setting.

Short Name: Web Server Status