How to find installation mode of Hadoop 2.x

what is the quickest way of finding the installation mode of the Hadoop 2.x?

I just want to learn the best way to find the mode when I login first time into a Hadoop installed machine.

Solution

In hadoop 2 - go to /etc/hadoop/conf folder and check the Fs.defaultFS in core-site.xml and Yarn.resourcemanager.hostname property in yarn-site.xml. The values for those properties decide which mode you are running in.

Fs.defaultFS

Standalone mode   - file:///
pseudo distributed- hdfs://localhost:8020/
Fully distributed - hdfs://namenodehostname:8020/

Yarn.resourcemanager.hostname

Standalone mode    - file:///
pseudo distributed - hdfs://localhost:8021/
Fully ditributed   - hdfs://resourcemanagerhostname:8021/

Alternatively you can use jps command to check the mode. if you see namenode/secondary namenode /jobtracker daemons running separately then it is distributed.

similarly in MR1 go to /etc/hadoop/conf folder and check the fs.default.name in core-site.xml and mapred.job.tracker property in mapred-site.xml.