无法启用 mysqld 服务，但重启后该服务在 centos 7 上运行

Question

安装后，我运行systemctl enable mysqld.service. 然后，输出是：

Failed to execute operation: Too many levels of symbolic links

出现此错误后，我重新启动了我的服务，并检查了 mysqld.service 的状态。 systemctl status mysqld.service -l

输出是

? mariadb.service - MariaDB database server
   Loaded: loaded (/usr/lib/systemd/system/mariadb.service; enabled; vendor preset: disabled)
  Drop-In: /etc/systemd/system/mariadb.service.d
           ??migrated-from-my.cnf-settings.conf
   Active: active (running) since Tue 2017-05-16 13:41:06 UTC; 8min ago
  Process: 1930 ExecStartPost=/bin/sh -c systemctl unset-environment _WSREP_START_POSITION (code=exited, status=0/SUCCESS)
  Process: 767 ExecStartPre=/bin/sh -c [ ! -e /usr/bin/galera_recovery ] && VAR= ||   VAR=`/usr/bin/galera_recovery`; [ $? -eq 0 ]   && systemctl set-environment _WSREP_START_POSITION=$VAR || exit 1 (code=exited, status=0/SUCCESS)
  Process: 743 ExecStartPre=/bin/sh -c systemctl unset-environment _WSREP_START_POSITION (code=exited, status=0/SUCCESS)
 Main PID: 813 (mysqld)
   Status: "Taking your SQL requests now..."
   CGroup: /system.slice/mariadb.service
           ??813 /usr/sbin/mysqld

May 16 13:41:05 hostname mysqld[813]: 2017-05-16 13:41:05 140294373226752 [Note] InnoDB: Highest supported file format is Barracuda.
May 16 13:41:06 hostname mysqld[813]: 2017-05-16 13:41:06 140294373226752 [Note] InnoDB: 128 rollback segment(s) are active.
May 16 13:41:06 hostname mysqld[813]: 2017-05-16 13:41:06 140294373226752 [Note] InnoDB: Waiting for purge to start
May 16 13:41:06 hostname mysqld[813]: 2017-05-16 13:41:06 140294373226752 [Note] InnoDB:  Percona XtraDB (http://www.percona.com) 5.6.35-80.0 started; log sequence number 1616859
May 16 13:41:06 hostname mysqld[813]: 2017-05-16 13:41:06 140293647075072 [Note] InnoDB: Dumping buffer pool(s) not yet started
May 16 13:41:06 hostname mysqld[813]: 2017-05-16 13:41:06 140294373226752 [Note] Plugin 'FEEDBACK' is disabled.
May 16 13:41:06 hostname mysqld[813]: 2017-05-16 13:41:06 140294373226752 [Note] Server socket created on IP: '::'.
May 16 13:41:06 hostname mysqld[813]: 2017-05-16 13:41:06 140294373226752 [Note] /usr/sbin/mysqld: ready for connections.
May 16 13:41:06 hostname mysqld[813]: Version: '10.1.23-MariaDB'  socket: '/var/lib/mysql/mysql.sock'  port: 3306  MariaDB Server
May 16 13:41:06 hostname systemd[1]: Started MariaDB database server.

反正是要解决问题？

谢谢！

Answer 1

删除mysqld.service符号链接/etc/systemd/system并mysqld.service再次启用：

rm /etc/systemd/system/mysqld.service
systemctl enable mysqld.service