In order to perform MapReduce on a Hadoop cluster, you have to install R and RHadoop on every task node. Here, we illustrate how to install rmr2 on a single node of a Hadoop cluster. First, open the terminal of the Cloudera QuickStart VM. Before installing rmr2, we first access an R session with root privileges and install dependent R packages.

Next, after all the dependent packages are installed, quit the R session and use the wget command in the Linux shell to download rmr-3.3.0 from GitHub to the local filesystem. You can then begin the installation of rmr2. Lastly, you can access an R session and use the library function to validate whether the package has been installed.