galera_new_cluster mariadb@<instnace_name> failed when wsrep_cluster_address already set some nodes address

I use "galera_new_cluster mariadb@node1" to bootstap a new cluster.

If set "wsrep_cluster_address="gcomm://" in config file, it is ok to startup a new cluster,
If set "wsrep_cluster_address="gcomm://10.10.10.1:4567,10.10.10.2:4567,10.10.10.3:4567" in config file, it will fail startup a new cluster.

I find a way to fix this problem:
edit "/usr/lib/systemd/system/mariadb@.service" file and append $_WSREP_NEW_CLUSTER in the end of "ExecStart="
then mariadb@.service can catch the environment variable _WSREP_NEW_CLUSTER="--wsrep-new-cluster" (setting in "galera_new_cluster" script)

After a "systemctl daemon-reload", then "galera_new_cluster mariadb@node1" will work fine to startup a new cluster.