My machine has 200G disk space in total but only close to 10g under the / directory. I keep getting errors that says "needs xx MB in the / file system" when installing HDP via Ambari. Is it possible to change the default HDP installation directories to other than the "/" directory ?
Ambari and HDP are installed via RPM files. Those RPMs do not support specifying an alternative install location (default location for HDP install is "/usr/hdp"). Your best option is probably to use symbolic links to another location. Means you can try to create a Symlink for "/usr/hdp" to another mount point. (But this will be just a workaround)
Or else it is better to make sure that "/" has enough space. Please refer to the Operating System tools to know how to increase the sapce of the root partition: