1. There are different Hadoop distributions . After Cloudera and Hortonworks merged , they are coming up with a common commercial distribution . Go to the Cloudera website and there are plenty of resources.
2.There are multiple components in a Hadoop cluster – Hive , Impala , Spark , Hue , Yarn , Cloudera Manager , navigator , HTTPFS , WEBHDFS, Hdfs , Hbase, Kudu , Kafka and zookeeper . Read about them .
3. Cloudera offers free images on their website . You need the virtual box software and atleast 16GB RAM on your PC. Download the image and upload into the virtual box. Rest is straight forward. The Cloudera website has detailed guidelines .
4.Practice configuring the cluster in your virtual Hadoop cluster .
5.If possible there are also multiple videos available in safari books online ( requires subscription) , free YouTube videos or paid courses in udemy and coursera.
6. A Hadoop expert should have strong Unix knowledge . This will help to troubleshoot issues between the various Hadoop services . You need to have through knowledge of Kerberos if you want to configure a secure cluster . You need to know about SSL.
