Hi Team,
Currently I am trying to REINDEX using Hadoop Mapreduce using the reference from Janus document.
https://docs.janusgraph.org/index-management/index-reindexing/#reindex-example-on-mapreduce

I wrote my implementation using Java. Here it is running fine. but it is running on Local mode.
For running on cluster mode I need to pass hadoop configurations but from documentations I am not clear how to pass any external configuration to run on hadoop or on yarn cluster.
If anybody has tried against a big graph like having a Billion of nodes, can you guide me on this?

My Java implementation:
JanusGraph janusGraph = JanusGraphFactory.open(janusConfig);
JanusGraphManagement management;
management = janusGraph.openManagement(); JanusGraphIndex graphIndex = management.getGraphIndex("AddressId");
MapReduceIndexManagement mapReduceIndexManagement = new MapReduceIndexManagement(janusGraph);
ScanMetrics scanMetrics = mapReduceIndexManagement.updateIndex(graphIndex, SchemaAction.REINDEX).get();

janusConfig:
gremlin.graph=org.janusgraph.core.JanusGraphFactory
storage.backend=cql
storage.hostname=127.0.0.1
storage.port=9042
storage.keyspace=janusgraph
cache.db-cache = false
cache.db-cache-clean-wait = 20
cache.db-cache-time = 180000
cache.db-cache-size = 0.25
index.search.backend=elasticsearch
index.search.hostname=127.0.0.1

Console log:
[INFO] 2021-02-17 13:37:55,173 LocalJobRunner Map Task Executor #0 org.apache.hadoop.mapred.LocalJobRunner - {} -
[INFO] 2021-02-17 13:37:56,141 task-1 org.apache.hadoop.mapreduce.Job - {} -  map 14% reduce 0%
[INFO] 2021-02-17 13:37:57,384 LocalJobRunner Map Task Executor #0 org.apache.hadoop.mapred.Task - {} - Task:attempt_local67526867_0001_m_000035_0 is done. And is in the process of committing
[INFO] 2021-02-17 13:37:57,384 LocalJobRunner Map Task Executor #0 org.apache.hadoop.mapred.LocalJobRunner - {} - map
[INFO] 2021-02-17 13:37:57,384 LocalJobRunner Map Task Executor #0 org.apache.hadoop.mapred.Task - {} - Task 'attempt_local67526867_0001_m_000035_0' done.
[INFO] 2021-02-17 13:37:57,385 LocalJobRunner Map Task Executor #0 org.apache.hadoop.mapred.Task - {} - Final Counters for attempt_local67526867_0001_m_000035_0: Counters: 16