you have installed hdp2.1 using ambari or manually ?
then you can use the doc i have mentioned in my answer and for information about how to add a service in ambari you can use this link
Thanks for your time...
looks like you have selected your own answer :)
packages will be there by default with HDP2.1 and then you will have to install them ,
if your hdp is ambari installed the follow:
if it is installed manually then follow this link: