As far as I can tell, Galera distributions these days should include the garbd arbitrator (http://www.codership.com/wiki/doku.php?id=galera_arbitrator) but that doesn't seem to be included in mariadb-galera-5.5.29-linux-x86_64 binary tarball.

Moreover, the package does not include the galera library itself, and it's not provided separately in MariaDB downloads, so someone who gets .tgz of mariadb-galera has nowhere to go to get the library.

Files :
garbd => bin/
libgalera_smm.so => lib/