Drill Configuration Files

The Drill installation includes configuration files with start-up options that you can modify prior to starting Drill.

The configuration files reside in a HOCON configuration file format, which is a hybrid between a properties file and a JSON file. The files have a nested relationship and a hierarchical structure, where one file overrides another. You can locate the files in the /opt/mapr/drill/drill-<version>/conf directory.

The configuration files are listed below in their hierarchical order. The drill-distrib.conf file overrides the drill-module.conf file, and the drill-override.conf file overrides the drill-distrib.conf file.
  • drill-override.conf
  • drill-distrib.conf
  • drill-module.conf
Environment variables are also overridden in the same way, in the order listed below:
  • drill-env.sh (or explicitly defined in environment)
  • distrib-env.sh
  • drill-config.sh
The following table lists the configuration files with their descriptions:
File Name Description Default Configuration with Secure Installation

Contains distribution-specific configurations for Drill. Automatically updated by configure.sh when you configure the cluster.

  • Enables authentication, impersonation, and encryption with MapR-SASL as the default mechanism.
  • Enables TLS for the HTTPS channel.
    Note: By default, HTTPS uses the SSL certificate provided by the cluster installation; however, an administrator can specify a certificate in a keystore.
  • Enables the inbound impersonation policy for administrators to impersonate any other user.
distrib-env.sh Contains distribution-specific defaults for various environment variables.
  • Enables authentication between the Drillbits and ZooKeeper.
  • Configures the location of the default security configuration file, mapr.login.conf, used by Drill.
drill-env.sh The drill-env.sh file contains the cluster admininstrator-specific environment variables that can differ from the defaults. You can modify this file to override the default values of system properties defined in the distrib-env.sh file or to define a new system property. For example, you can configure the amount of heap and direct memory allocated to Drill. See Configuring Drill Memory. Empty upon installation.

Use the drill-override.conf file to override the default values obtained from drill-module.conf and drill-distrib.conf. A cluster administrator can update this file to configure a Drillbit as required (different from default installation)

When you first install Drill, drill-override.conf contains ZooKeeper and Drillbit configuration information; however, after you run configure.sh -R, the entries are removed and the file does not contain any configurations.