Understanding ASM (6) ASM file management

① ASM file conversion

Take the created asmtest tablespace as an example.

(I) convert OS files to ASM files

Sys @ ORCL> create tablespace asmtest datafile size 10 m;

Tablespace created.

Sys @ ORCL> alter tablespace asmtest offline;

Tablespace altered.

[Oracle @ localhost ~] $ Rman target/

RMAN> backup as copy tablespace asmtest format '+ data ';

RMAN> switch tablespace asmtest to copy;

Datafile 6 switched to datafile copy "+ DATA/orcl/datafile/asmtest.256.798497595"

Sys @ ORCL> alter tablespace asmtest online;

Tablespace altered.

Sys @ ORCL> select file_name from dba_data_files where tablespace_name = 'asmtest ';

FILE_NAME

Bytes ----------------------------------------------------------------------------------------------------

+ DATA/orcl/datafile/asmtest.256.798497595

ASMCMD> mkalias ASMTEST.256.798497595 asmtest. dbf

ASMCMD> ls-al

Type Redund Striped Time Sys Name

Datafile mirror coarse nov 04 20:00:00 Y + DATA/ORCL/DATAFILE/asmtest. dbf => ASMTEST.256.798497595

N asmtest. dbf => + DATA/ORCL/DATAFILE/ASMTEST.256.798497595

(Ii) migrate data files from one diskgroup to another diskgroup

Idle> select file_id from dba_data_files where tablespace_name = 'asmtest ';

FILE_ID

----------

6

Idle> alter tablespace asmtest offline;

[Oracle @ localhost ~] $ Rman target/

RMAN> backup as copy datafile 6 format' + THINK ';

RMAN> switch datafile 6 to copy;

RMAN> recover datafile 6;

RMAN> SQL "alter tablespace asmtest online ";

ASMCMD> find THINK /*

+ THINK/ORCL/

+ THINK/ORCL/DATAFILE/

+ THINK/ORCL/DATAFILE/ASMTEST.256.798503425

(3) Forward the ASM file to the OS file

Sys @ ORCL> select file_name from dba_data_files where tablespace_name = 'asmtest ';

FILE_NAME

Bytes ----------------------------------------------------------------------------------------------------

+ THINK/orcl/datafile/asmtest.256.798503425

Sys @ ORCL> alter tablespace asmtest offline;

Sys @ ORCL> create directory ossrc as '/home/oracle ';

Sys @ ORCL> create directory asmsrc as '+ THINK/orcl/datafile ';

Sys @ ORCL> begin

2 dbms_file_transfer.copy_file ('asmsrc ', 'asmtest. 000000', 'ossrc', 'asm. dbf ');

3 end;

4/

PL/SQL procedure successfully completed.

Sys @ ORCL> alter database rename file '+ THINK/orcl/datafile/asmtest.256.798503425' to '/home/oracle/ASM. dbf ';

[Oracle @ localhost ~] $ Rman target/

RMAN> recover datafile 6;

RMAN> SQL "alter tablespace asmtest online ";

Sys @ ORCL> select file_name from dba_data_files where tablespace_name = 'asmtest ';

FILE_NAME

Bytes ----------------------------------------------------------------------------------------------------

/Home/oracle/ASM. DBF

② File name in ASM

ASM file name, such:

+ THINK/orcl/datafile/asmtest.256.798503425

The above names are generated in the following format:

+ Diskgroup/dbname/file_type/file_type_tag.file.incarnation

● + Diskgroup: disk group name

● Dbname: Database DB_UNIQUE_NAME parameter value

● File_type: the type of the created file, such as CONTROLFILE/DATAFILE/ONLINELOG/ARCHIVELOG/TEMPFILE/BACKUPSET/FLASHBACK.

● File_type_tag: file type label. For example, the tablespace name is usually

● File. incarnation: file number + incarnation, used to ensure that the file is unique

The actual file name and path cannot be specified during file creation. It is completely controlled and managed by oracle omf.

For example:

Sys @ ORCL> alter tablespace asmtest add datafile '+ data' size 10 m;

Tablespace altered.

If the initialization parameter db_create_file_dest is set, you do not need to write the disk name.

Other types of files, such as redo log files, are operated in the same way.

However, trace files, alert files, and dump files cannot be directly stored in ASM.

Oracle video tutorial follow: http://u.youku.com/user_video/id_UMzAzMjkxMjE2.html