$ sudo apt-get update
$ sudo apt-get install fusiondirectory-schema 

fusiondirectory-schema is installed in your system.

Make ensure the fusiondirectory-schema package were installed using the commands given below,

$ sudo dpkg-query -l | grep fusiondirectory-schema *

You will get with fusiondirectory-schema package name, version, architecture and description in a table

fusiondirectory-schema package basic information: