How to modify ASM disk redundancy 03/29 Update SLTechnology News&Howtos

How to modify ASM disk redundancy

2025-03-29 Update From: SLTechnology News&Howtos shulou NAV: SLTechnology News&Howtos > Database >

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Editor to share with you how to modify ASM disk redundancy, I believe that most people do not know much about it, so share this article for your reference, I hope you can learn a lot after reading this article, let's go to know it!

Rummaged through the official documents:

Automatic Storage Management Administrator's Guide->

4 Administering Oracle ASM Disk Groups->

Using the CREATE DISKGROUP SQL Statement-> Specify the redundancy level of the disk group.

After a disk group is created, you cannot alter the redundancy level of the disk group. To change the redundancy level, you must create another disk group with the appropriate redundancy and then move the files to the new disk group.

After an ASM disk group is created, the redundancy level of the disk group cannot be modified. If you want to change the redundancy level of a disk group, you must create another disk group with the appropriate redundancy level, and then move the data to the new disk group.

Official documentation link: http://docs.oracle.com/cd/E11882_01/server.112/e18951/asmdiskgrps.htm#CHDBDAGI

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So there is the following experiment:

Since the previous virtual machine environment is 10gASM (the next time it is tested with 11g, the steps should be about the same), and the database is stored on + DATA disk, and the redundancy set by + DATA disk is regular redundancy, so this lab will change from regular redundancy to external redundancy.

The change of external redundancy to regular redundancy is basically consistent with the procedure of this experiment.

# # #

Migration steps:

First create a new ASM disk group.

First migrate the control files to the disk group, then migrate the data files, log files, and so on.

# # #

Create a new disk group

10g use dbca,11g with asmca, or directly with instructions. Here I use dbca:

Check the disk group:

Click (here) to collapse or open

[root@oracle4 ~] # su-oracle

[oracle@oracle4 ~] $export ORACLE_SID=+ASM

[oracle@oracle4 ~] $sqlplus / as sysdba

SQL*Plus: Release 10.2.0.1.0-Production on Wed Aug 19 01:17:26 2015

Connected to:

Oracle Database 10g Enterprise Edition Release 10.2.0.1.0-Production

With the Partitioning, OLAP and Data Mining options

SQL > select state,name,type from v$asm_diskgroup

STATE NAME TYPE

MOUNTED DATA NORMAL

MOUNTED RECOVER EXTERN

MOUNTED NEWDG EXTERN

-here, we created a new ASM disk group called NEWDG, which is externally redundant.

Migrate control files to a new disk group

Environment: old control files on + data disk group, new on + newdg disk group

Migration method: first add a control file to + newdg, and then delete the old control file on + data disk

The migration steps are as follows:

-1. Change the parameters of the control file from one path on the + DATA disk to two paths in the parameter file

SQL > alter system set control_files='+DATA/asmdb/controlfile/current.260.886430449','+newdg' scope=spfile

-2. After changing to two paths, an error will be reported because the second file does not exist.

-restart the database to nomount mode and restore the second control file from the first control file using rman

SQL > startup force nomount

ORACLE instance started.

Total System Global Area 608174080 bytes

Fixed Size 1220844 bytes

Variable Size 180358932 bytes

Database Buffers 423624704 bytes

Redo Buffers 2969600 bytes

[oracle@oracle4 dbs] $rman target /

Recovery Manager: Release 10.2.0.1.0-Production on Wed Aug 19 01:47:18 2015

Connected to target database: asmdb (not mounted)

RMAN > restore controlfile from'+ DATA/asmdb/controlfile/current.260.886430449'

Starting restore at 19-AUG-15

Using target database control file instead of recovery catalog

Allocated channel: ORA_DISK_1

Channel ORA_DISK_1: sid=156 devtype=DISK

Channel ORA_DISK_1: copied control file copy

Output filename=+DATA/asmdb/controlfile/current.260.886430449

Output filename=+NEWDG/asmdb/controlfile/backup.257.888112073

Finished restore at 19-AUG-15

-marked in red is the generated new control file

-at this point, start the database to nomount mode

-you will find that the parameters have been modified:

RMAN > alter database mount

Database mounted

Released channel: ORA_DISK_1

[oracle@oracle4 dbs] $sqlplus / as sysdba

SQL*Plus: Release 10.2.0.1.0-Production on Wed Aug 19 01:48:48 2015

Connected to:

Oracle Database 10g Enterprise Edition Release 10.2.0.1.0-Production

With the Partitioning, OLAP and Data Mining options

SQL > show parameter control

NAME TYPE VALUE

Control_file_record_keep_time integer 7

Control_files string + DATA/asmdb/controlfile/curren

T.260.886430449, + NEWDG/asmdb/controlfile/backup.257.888112073

The new control file parameter changes to the location of the control file that was previously restored by rman, as follows:

+ DATA/asmdb/controlfile/current.260.886430449-this is old

+ NEWDG/asmdb/controlfile/backup.257.888112073-this is the new location to which we need to be migrated, we find that the control file has been migrated to the new location, and then we need to delete the old control file

-3. Delete the old control file, so remove it from the control file parameters:

SQL > alter system set control_files='+NEWDG/asmdb/controlfile/backup.257.888112073' scope=spfile

System altered.

SQL > startup force

ORACLE instance started.

Total System Global Area 608174080 bytes

Fixed Size 1220844 bytes

Variable Size 180358932 bytes

Database Buffers 423624704 bytes

Redo Buffers 2969600 bytes

Database mounted.

Database opened.

SQL > show parameter control

NAME TYPE VALUE

Control_file_record_keep_time integer 7

Control_files string + NEWDG/asmdb/controlfile/backup.257.888112073

At this point, the control file was successfully moved to the + NEWDG disk.

Migrate data files to a new disk group

Environment: old data files on + data disk group, new data on + newdg disk group

Migration method: first make a mirror copy of the data file on + newdg, and then do switch to tell the control file that our data file is on + newdg, not on + data disk.

The migration steps are as follows:

-1. Copy data file

[oracle@oracle4 dbs] $rman target /

Recovery Manager: Release 10.2.0.1.0-Production on Wed Aug 19 01:51:13 2015

Connected to target database: ASMDB (DBID=630629232)

RMAN > backup as copy database format'+ newdg'

Starting backup at 19-AUG-15

Using target database control file instead of recovery catalog

Allocated channel: ORA_DISK_1

Channel ORA_DISK_1: sid=144 devtype=DISK