MapR-specific requirements

If you have MapR, your system must meet a few additional requirements.

The MapR Client must be installed and added to the $PATH on all non-MapR nodes that will host the Dgraph, Studio, and the Transform Service (if different from Studio nodes). Note that the Client isn't required on these nodes if they host any MapR processes.
For instructions on installing the MapR Client, see Installing the MapR Client in MapR's documentation.
Pluggable authentication modules (PAMs) must be disabled for the installation.
The yarn.resourcemanager.hostname property in yarn-site.xml must be set to the fully-qualified domain name (FQDN) of your YARN ResourceManager. For instructions on updating this property, see Updating the YARN ResourceManager configuration.
The directories /user/HDFS_DP_USER_DIR/<bdd> and /user/HDFS_DP_USER_DIR/edp/data must be either nonexistent or mounted with a volume. HDFS_DP_USER_DIR is defined in BDD's configuration file, and <bdd> is be the name of the bdd user.
The /opt/mapr/zkdata and /opt/mapr/zookeeper/zookeeper-3.4.5/logs directories must have their permissions set to 755.
If you want to store your Dgraph databases on MapR-FS, the directory defined by DGRAPH_INDEX_DIR in BDD's configuration file must be either nonexistent or mounted with a volume. Additionally, the MapR NFS service must be installed on all nodes that will host the Dgraph. For more information, see HDFS.
The required Spark, ZooKeeper, and Hive patches must be installed as described in Applying the MapR patches.