Oracle DB 12c新特性：raw device 裸设备不再受支持

阿尔海南粉

　　Oracle DB 12c新特性：raw device 不再受支持。
　　参考自：

Announcement of De-Support of using RAW devices in Oracle Database Version 12.1 (Doc ID 578455.1)
　　细节：

De-Support of Raw

本文的目录是通知在oracle database 12.1版本中对raw device不再支持。

这意味着，若是使用oracle database 12.1版本，将不能把数据文件，OCR 或者 voting disk 放在raw devices上，即使升级到这个版本中也不行。
　　原因：

In the past, clustered databases required raw devices. However raw devices were cumbersome to manage and are no longer required.
　　

Details of the Announcement
　　Starting with Oracle Database version 12.1 (release date TBD), support for storing data files, spfiles, controlfiles, online redo logfiles, OCRs and voting files on raw devices directly will end. This means commands such as the following will report an error
while attempting to use raw devices directly in Oracle Database Version 12.1:

SQL> create tablespace ABC DATAFILE '/dev/raw/raw1' size 2GB;
　　Note that while the direct use of raw devices will be de-supported for Oracle Database 12.1, customers can choose to create Oracle ASM diskgroups on top of raw devices. While it is recommended to store all shared files on ASM diskgroups, storing those files
on NFS or certified cluster file systems remains supported.

--->看到这句话，虽然说认证通过的集群文件系统仍然受到支持，比如veritas storage foundation,但是谁能保证在未来的版本中还支持cluster file systems呢？veritas 看到这句话，一定有一种唇亡齿寒的感觉。
　　The following SQL commands will not return an error while attempting to use raw devices. Reason: the raw devices in the example below are used indirectly via Oracel ASM (no direct use of raw devices here):

SQL>alter diskgroup MYDG add disk '/dev/raw/ABC1.dbf';
OR
SQL>create diskgroup MYDB EXTERNAL REDUNDANCY disk 'dev/raw/ABC1.dbf'
Then use the following command to create the tablespace
SQL> create tablespace ABC DATAFILE '+MYDG' size 2GB;

　　Actions
　　If raw devices are not being used directly in the current release then no further actions need to be taken. However, if raw devices are being used directly currently, then planning should be performed to migrate respective files off raw devices. There are
many choices currently to replace raw devices, including Oracle ASM, NFS, and supported cluster file systems.
　　

For more information on supported NFS or cluster file system,

go to support.oracle.com -> Certifications
　　This announcement applies to both, Oracle Single Instance and Oracle Real Application Clusters (RAC) databases.
　　-->对单机和rac都不支持裸设备了。