Documentation

Table of Contents API documentation

HDFS

Make sure to include druid-hdfs-storage as an extension.

Deep Storage

Configuration

Property Possible Values Description Default
druid.storage.type hdfs Must be set.
druid.storage.storageDirectory Directory for storing segments. Must be set.
druid.hadoop.security.kerberos.principal druid@EXAMPLE.COM Principal user name empty
druid.hadoop.security.kerberos.keytab /etc/security/keytabs/druid.headlessUser.keytab Path to keytab file empty

If you are using the Hadoop indexer, set your output directory to be a location on Hadoop and it will work. If you want to eagerly authenticate against a secured hadoop/hdfs cluster you must set druid.hadoop.security.kerberos.principal and druid.hadoop.security.kerberos.keytab, this is an alternative to the cron job method that runs kinit command periodically.

Google Cloud Storage

The HDFS extension can also be used for GCS as deep storage.

Configuration

Property Possible Values Description Default
druid.storage.type hdfs Must be set.
druid.storage.storageDirectory gs://bucket/example/directory Must be set.

All services that need to access GCS need to have the GCS connector jar in their class path. One option is to place this jar in /lib/ and /extensions/druid-hdfs-storage/

Tested with Druid 0.9.0, Hadoop 2.7.2 and gcs-connector jar 1.4.4-hadoop2.