Output of 'sudo docker logs elasticsearch' is below ::
[2016-03-25 19:05:15,465][INFO ][node ] [STG1 - Wolverine] version[2.1.1], pid[1], build[40e2c53/2015-12-15T13:05:55Z]
[2016-03-25 19:05:15,466][INFO ][node ] [STG1 - Wolverine] initializing ...
[2016-03-25 19:05:15,523][INFO ][plugins ] [STG1 - Wolverine] loaded [], sites []
[2016-03-25 19:05:15,562][INFO ][env ] [STG1 - Wolverine] using [1] data paths, mounts [[/data (/dev/md127)]], net usable_space [1.8tb], net total_space [1.9tb], spins? [possibly], types [ext4]
Exception in thread "main" java.nio.file.FileAlreadyExistsException: /data/elasticsearch_data/NonProdSTG/nodes/0/__es__.tmp
at sun.nio.fs.UnixException.translateToIOException(UnixException.java:88)
at sun.nio.fs.UnixException.rethrowAsIOException(UnixException.java:102)
at sun.nio.fs.UnixException.rethrowAsIOException(UnixException.java:107)
at sun.nio.fs.UnixFileSystemProvider.newByteChannel(UnixFileSystemProvider.java:214)
at java.nio.file.Files.newByteChannel(Files.java:361)
at java.nio.file.Files.createFile(Files.java:632)
at org.elasticsearch.env.NodeEnvironment.ensureAtomicMoveSupported(NodeEnvironment.java:750)
at org.elasticsearch.gateway.GatewayMetaState.<init>(GatewayMetaState.java:82)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:422)
at <<<guice>>>
at org.elasticsearch.node.Node.<init>(Node.java:200)
at org.elasticsearch.node.Node.<init>(Node.java:128)
at org.elasticsearch.node.NodeBuilder.build(NodeBuilder.java:145)
at org.elasticsearch.bootstrap.Bootstrap.setup(Bootstrap.java:178)
at org.elasticsearch.bootstrap.Bootstrap.init(Bootstrap.java:285)
at org.elasticsearch.bootstrap.Elasticsearch.main(Elasticsearch.java:35)
[2016-03-25 19:05:20,276][INFO ][node ] [STG1 - Wolverine] version[2.1.1], pid[1], build[40e2c53/2015-12-15T13:05:55Z]
[2016-03-25 19:05:20,277][INFO ][node ] [STG1 - Wolverine] initializing ...
[2016-03-25 19:05:20,331][INFO ][plugins ] [STG1 - Wolverine] loaded [], sites []
[2016-03-25 19:05:20,359][INFO ][env ] [STG1 - Wolverine] using [1] data paths, mounts [[/data (/dev/md127)]], net usable_space [1.8tb], net total_space [1.9tb], spins? [possibly], types [ext4]