Steps:

1. Copy glusterfs-2.0.0rc1.tar.gz into /usr/ports/distfiles
2. cd glusterfs/
3. make install 
4. make package
5. pkg_add glusterfs-2.0.0rc1_1.tbz

To uninstall
1. make deinstall 
2. pkg_delete glusterfs-2.0.0rc1_1