To shut down an Oracle ASM instance, perform the following steps:

For more information about user authentication, see "Authentication for Accessing Oracle ASM Instances".

The following list describes the SHUTDOWN modes and the behavior of the Oracle ASM instance in each mode.

• NORMAL Clause

  Oracle ASM waits for any in-progress SQL to complete before performing an orderly dismount of all of the disk groups and shutting down the Oracle ASM instance. Before the instance is shut down, Oracle ASM waits for all of the currently connected users to disconnect from the instance. If any database instances are connected to the Oracle ASM instance, then the SHUTDOWN command returns an error and leaves the Oracle ASM instance running. NORMAL is the default shutdown mode.
  ASM等待正在执行的SQL完成操作、所有用户断开连接才停止实例，如果有DB继续连着该实例，那么该操作出错
  

• IMMEDIATE or TRANSACTIONAL Clause

  Oracle ASM waits for any in-progress SQL to complete before performing an orderly dismount of all of the disk groups and shutting down the Oracle ASM instance. Oracle ASM does not wait for users currently connected to the instance to disconnect. If any database instances are connected to the Oracle ASM instance, then the SHUTDOWN command returns an error and leaves the Oracle ASM instance running. Because the Oracle ASM instance does not contain any transactions, the TRANSACTIONAL mode behaves the same as IMMEDIATE mode.
  ASM等待所有正在执行的SQL完成后进行dismount和停止实例的操作，不等待用户断开连接，同样如果还有DB实例连接到ASM实例，那么停止操作出错，
  必须等到DB实例断开才正常关闭ASM实例
  

• ABORT Clause

  The Oracle ASM instance immediately shuts down without the orderly dismount of disk groups. This causes recovery to occur upon the next Oracle ASM startup.

  If any database instance is connected to the Oracle ASM instance, then the database instance aborts.

  If any Oracle Automatic Storage Management Cluster File System (Oracle ACFS) file systems are currently mounted on Oracle ADVM volumes, those file systems should first be dismounted. Otherwise, applications encounter I/O errors and Oracle ACFS user data and metadata may not be written to storage before the Oracle ASM storage is fenced. For information about dismounting an Oracle ACFS file system, see "Deregistering, Dismounting, and Disabling Volumes and Oracle ACFS File Systems". For more information about user authentication on Oracle ASM instance, see "Authentication for Accessing Oracle ASM Instances".
  
  这种情况下ASM实例和连接的DB实例都异常关闭，下次启动需要恢复，慎用。