我已经开始使用cassandra，因此已成功在Centos 7中安装了Cassandra。现在，我面临重新启动/停止cassandra服务的问题。
systemctl start cassandra 命令运行正常。但是 systemctl重新启动cassandra 和 systemctl停止cassandra 无法正常工作，
下面是命令的响应：systemctl status cassandra
Response:
● cassandra.service - SYSV: Starts and stops Cassandra
Loaded: loaded (/etc/rc.d/init.d/cassandra; bad; vendor preset: disabled)
Active: active (exited) since Tue 2018-11-20 07:38:23 UTC; 2s ago
Docs: man:systemd-sysv-generator(8)
Process: 15611 ExecStop=/etc/rc.d/init.d/cassandra stop (code=exited, status=1/FAILURE)
Process: 15641 ExecStart=/etc/rc.d/init.d/cassandra start (code=exited, status=0/SUCCESS)
Nov 20 07:38:23 DE-Cassandra01 systemd[1]: Starting SYSV: Starts and stops Cassandra...
Nov 20 07:38:23 DE-Cassandra01 su[15650]: (to cassandra) root on none
Nov 20 07:38:23 DE-Cassandra01 systemd[1]: Started SYSV: Starts and stops Cassandra.
Nov 20 07:38:23 DE-Cassandra01 cassandra[15641]: Starting Cassandra: OK