not able to start bootstrap service in centos 7

iI am trying to setup percona xtradb mysql cluster version. i have downloaded the tar from the site and now trying to run systemctl start mysql@bootstrap.service
but given error as - [root@localhost Downloads]# systemctl start mysql@bootstrap.service
Failed to start mysql@bootstrap.service: Unit not found.
[root@localhost Downloads]# service mysql status
Redirecting to /bin/systemctl status mysql.service
Unit mysql.service could not be found.

can you please let me know if i am missing something?