centos7无法自启动 mysql怎么解决？

阿里云ecs 安装了mysql 5.6，使用 systemctl start mysql成功启动mysql，可使用 systemctl enable mysql将mysql加入到开机自启动，可却报错：

[root@go ~]# mysql -v
mysql  ver 14.14 distrib 5.6.29, for linux (x86_64) using  editline wrapper
[root@go ~]#
[root@go ~]# systemctl enable mysql
failed to execute operation: no such file or directory
[root@go ~]# systemctl enable mariadb
failed to execute operation: no such file or directory
[root@go ~]#

使用systemctl enable mariadb 也是一样的，我在linode中的centos7是直接使用 systemctl enable mariadb 加入自启动的

但是运行 systemctl enable httpd 是没有报错。

[root@go ~]# chkconfig

note: this output shows sysv services only and does not include native
      systemd services. sysv configuration data might be overridden by native
      systemd configuration.

      if you want to list systemd services use 'systemctl list-unit-files'.
      to see services enabled on particular target use
      'systemctl list-dependencies [target]'.

aegis           0:off   1:off   2:on    3:on    4:on    5:on    6:off
agentwatch      0:off   1:off   2:on    3:on    4:on    5:on    6:off
netconsole      0:off   1:off   2:off   3:off   4:off   5:off   6:off
network         0:off   1:off   2:on    3:on    4:on    5:on    6:off
[root@go ~]#