Cloudera Docs

Impala Logs

You can review Impala log files on each host, when you have traced an issue back to a specific system. The Impala logs contain information about any errors Impala encountered, jobs Impala has completed, and settings Impala is configured with.

The logs store information about Impala startup options. This information appears once for each time Impala is started and may include:

  • Machine name.
  • Impala version number.
  • Flags used to start Impala.
  • CPU information.
  • The number of available disks.

A new set of log files is produced each time the associated daemon is restarted. These log files have long names including a timestamp. The .INFO, .WARNING, and .ERROR files are physically represented as symbolic links to the latest applicable log files.

Review Impala log files on each host, when you have traced an issue back to a specific system:

  • By using the web interface at http://host-name:25000/logs where host-name is your Cloudera cluster host name.

    The web interface limits the amount of logging information displayed. To view every log entry, access the log files directly through the file system. Impala log files can often be several megabytes in size.

  • By examining the contents of the log file

    By default, the Impala logs are stored at /var/log/impalad/, /var/log/catalogd/, and /var/log/statestore/. The most comprehensive log, showing informational, warning, and error messages, is in the file name impalad.INFO.

    For each of impalad, statestored, catalogd:

    • Examine the .INFO files to see configuration settings for the processes.
    • Examine the .WARNING files to see all kinds of problem information, including such things as suboptimal settings and also serious runtime errors.
    • Examine the .ERROR and/or .FATAL files to see only the most serious errors, if the processes crash, or queries fail to complete. These messages are also in the .WARNING file.

Cloudera Manager collects front-end and back-end logs together into a single view and let you do a search across log data for all the managed nodes in Diagnostics > Logs.