Shulou(Shulou.com)05/31 Report--

This article mainly introduces "what are the management and maintenance methods of ASM under Oracle11g RAC". In the daily operation, I believe that many people have doubts about the management and maintenance methods of ASM under Oracle11g RAC. The editor consulted all kinds of materials and sorted out simple and easy-to-use operation methods. I hope it will be helpful to answer the doubts about "what are the management and maintenance methods of ASM under Oracle11g RAC?" Next, please follow the editor to study!

First, basic maintenance:

Note: the following commands and procedures other than OS can be managed by ASM-related operations and Oracle Enterprise Mananger in ASMCA.

1. View ASM disks and disk groups:

-- SQL to see which disk groups are available.

[root@rac01 ~] # su-grid

[grid@rac01 ~] $sqlplus "/ as sysasm"

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

GROUP_NUMBER NAME STATE TYPE

-

1 OCR_VOTE MOUNTED EXTERN

2 ORADATA MOUNTED EXTERN

3 ORAFLASH MOUNTED EXTERN

The space usage of the disk group can be seen through some fields such as total_mb and free_mb.

-- View ASM disk through SQL statement

SQL > set line 2000

SQL > select group_number, name,failgroup, path from v$asm_disk

GROUP_NUMBER NAME FAILGROUP PATH

-

2 ASMDATA01 ASMDATA01 ORCL:ASMDATA01

3 ASMDATA02 ASMDATA02 ORCL:ASMDATA02

1 OCR_VOTE01 OCR_VOTE01 ORCL:OCR_VOTE01

Disks can be associated with disk groups through group_number (a disk group can correspond to multiple disks).

Here, you can see that disk OCR_VOTE01 corresponds to OCR_VOTE disk group, disk ASMDATA01 corresponds to ORADATA disk group, and disk ASMDATA02 corresponds to ORAFLASH disk group (it is recommended to have the same name).

-- View disk groups through asmcmd (each disk group appears as a directory):

[root@rac01 ~] # su-grid

[grid@rac01 ~] $asmcmd

ASMCMD > ls-al

State Type Rebal Name

MOUNTED EXTERN N OCR_VOTE/

MOUNTED EXTERN N ORADATA/

MOUNTED EXTERN N ORAFLASH/

Remarks: or ASMCMD > lsdg

View the ASM disk through the oracleasm command under OS.

[root@rac01 bin] # / usr/sbin/oracleasm listdisks

ASMDATA01

ASMDATA02

OCR_VOTE01

two。 Learn about ASM-related paths:

Through the asmcm command, you can see that ASM will establish some default paths under the ORADATA disk group according to the datafile path established by DBCA (generally, ARCHIVELOG/, CONTROLFILE/,DATAFILE/, ONLINELOG/, PARAMETERFILE/, TEMPFILE/, directories under db_name are all uppercase, in which the lowercase arch is built by the user, the SYS field is Y, and N is defined by the user)

[root@rac01 bin] # su-grid

[grid@rac01 ~] $asmcmd

ASMCMD > ls

OCR_VOTE/

ORADATA/

ORAFLASH/

ASMCMD > cd oradata

ASMCMD > ls

RACDB/

ASMCMD > cd racdb

ASMCMD > ls-l

Type Redund Striped Time Sys Name

Y ARCHIVELOG/

Y CONTROLFILE/

Y DATAFILE/

Y ONLINELOG/

Y PARAMETERFILE/

Y TEMPFILE/

N arch/

N control01.ctl = > + ORADATA/RACDB/CONTROLFILE/Current.256.739387263

N control02.ctl = > + ORADATA/RACDB/CONTROLFILE/Current.257.739387265

N redo01.log = > + ORADATA/RACDB/ONLINELOG/group_1.258.739387273

N redo02.log = > + ORADATA/RACDB/ONLINELOG/group_2.259.739387281

N redo03.log = > + ORADATA/RACDB/ONLINELOG/group_3.266.739393547

N redo04.log = > + ORADATA/RACDB/ONLINELOG/group_4.267.739393547

N spfileracdb.ora = > + ORADATA/RACDB/PARAMETERFILE/spfile.268.739393555

ASMCMD >

-- Archive path ARCHIVELOG:

See the archive path from the oracle database parameter file:

SQL > show parameter log_archive_dest

Log_archive_dest_1 string LOCATION=+ORADATA/RACDB/arch

You can see the archive path "+ ORADATA/RACDB/arch", then + ORADATA/RACDB/ARCHIVELOG

What kind of files are saved below?

ASMCMD > pwd

+ oradata/racdb/arch-View the archive path in the parameter

ASMCMD > ls-l

Type Redund Striped Time Sys Name

N 1_204_739387258.arc = >

+ ORADATA/RACDB/ARCHIVELOG/2011_11_28/thread_1_seq_204.478.768441403

N 1_205_739387258.arc = >

+ ORADATA/RACDB/ARCHIVELOG/2011_11_29/thread_1_seq_205.481.768443221

N 1_206_739387258.arc = >

+ ORADATA/RACDB/ARCHIVELOG/2011_11_29/thread_1_seq_206.482.768443233

N 1_207_739387258.arc = >

+ ORADATA/RACDB/ARCHIVELOG/2011_11_29/thread_1_seq_207.483.768443239

The user-defined archive format and archive path point to the directories and files automatically established by ASM. The custom generated archive is equivalent to a shortcut (or soft connection), and the actual file is the archive file of the ASM default path.

You can also manually generate aliases for Oracle ASM Filename:

ALTER DISKGROUP ORADATA ADD ALIAS

'+ oradata/racdb/datafile/test01.dbf'

FOR'+ oradata/racdb/datafile/TEST.340.740166807'

ASMCMD > pwd

+ oradata/racdb/ARCHIVELOG-View the default archive path of the ASM system

ASMCMD > ls-l

Type Redund Striped Time Sys Name

Y 2011_11_28/

Y 2011_11_29/

Y 2011_11_30/

Archived files are stored on a daily basis and are cataloged separately.

ASMCMD > cd 2011 / 11 / 29 /

ASMCMD > ls-l

Type Redund Striped Time Sys Name

ARCHIVELOG UNPROT COARSE NOV 29 00:00:00 Y thread_1_seq_205.481.768443221

ARCHIVELOG UNPROT COARSE NOV 29 00:00:00 Y thread_1_seq_206.482.768443233

ARCHIVELOG UNPROT COARSE NOV 29 00:00:00 Y thread_1_seq_207.483.768443239

ARCHIVELOG UNPROT COARSE NOV 29 00:00:00 Y thread_1_seq_208.485.768443253

ARCHIVELOG UNPROT COARSE NOV 29 00:00:00 Y thread_1_seq_209.486.768443277

-- Control the file path CONTROLFILE:

ASMCMD > cd racdb

ASMCMD > ls-l

Type Redund Striped Time Sys Name

N control01.ctl = > + ORADATA/RACDB/CONTROLFILE/Current.256.739387263

N control02.ctl = > + ORADATA/RACDB/CONTROLFILE/Current.257.739387265

Check the location of the initialization parameter file. The actual file is similar to the soft link method:

SQL > show parameter control

NAME TYPE VALUE

-

Control_files string + ORADATA/racdb/control01.ctl

+ ORADATA/racdb/control02.ctl

How to add control files? Examples are as follows:

SQL > alter database mount database

SQL > alter database backup controlfile to'+ ORADATA/racdb/control02.ctl'

SQL > alter database backup controlfile to'+ ORADATA/racdb/control03.ctl'

SQL > alter system set control_files='+ORADATA/racdb/control01.ctl','+DATA/racdb/control02.ctl','+DATA/racdb/control03.ctl'

Scope=spfile

SQL > startup mount

-- data file path DATAFILE:

ASMCMD > pwd

+ oradata/racdb/datafile

ASMCMD >

ASMCMD > ls-l

Type Redund Striped Time Sys Name

DATAFILE UNPROT COARSE OCT 29 18:00:00 Y BASE_DATA.317.754072293

DATAFILE UNPROT COARSE OCT 29 18:00:00 Y BASE_DATA.318.754072319

DATAFILE UNPROT COARSE OCT 29 18:00:00 Y BASE_DATA.319.754072331

DATAFILE UNPROT COARSE OCT 29 18:00:00 Y BASE_DATA.320.754072345

N BASE_DATA01.DBF = > + ORADATA/RACDB/DATAFILE/BASE_DATA.317.754072293

N BASE_DATA02.DBF = > + ORADATA/RACDB/DATAFILE/BASE_DATA.318.754072319

N BASE_DATA03.DBF = > + ORADATA/RACDB/DATAFILE/BASE_DATA.319.754072331

N BASE_DATA04.DBF = > + ORADATA/RACDB/DATAFILE/BASE_DATA.320.754072345

You can see that the name of the link and the name of the corresponding entity file appear in the datafile directory. Of course, not every entity file has a corresponding linked file name. For example, when you specify a + ORADATA disk group when you initially set up the database, the database will automatically establish the initial data file. At that time, the file is only system-generated, and there is no user-specified name (link name). For example, LOGMNRTS.321.754072935, SYSTEM.263.754063787 and so on in the above example.

When joining the datafile or establishing a table space, if you only specify + ORADATA and do not clearly write the path and file name, then the system self-built file will be generated without the link name, and if the file uses a similar'+ ORADATA/racdb/datafile/mytbs01.dbf', then the system self-built file and the corresponding link file will be generated.

You can also use ALTER DISKGROUP XX ADD ALIAS to add aliases.

-- recognize the file name

BASE_DATA.317.754072293 is the table space name + file number. Incarnation.

+ group/dbname/file type/tag.file.incarnation format is the disk group name, file type is the Oracle file type, tag is generally for a table space name, file.incarnation is combined to ensure uniqueness.

Testing: adding data files or tablespaces

CREATE TABLESPACE MYTBS DATAFILE

'+ ORADATA/racdb/datafile/mytbs01.dbf' SIZE 10m AUTOEXTEND OFF

LOGGING

ONLINE

PERMANENT

EXTENT MANAGEMENT LOCAL UNIFORM. SIZE 5M

BLOCKSIZE 16K

SEGMENT SPACE MANAGEMENT AUTO

FLASHBACK ON

Or

CREATE TABLESPACE TONYTBS DATAFILE

'+ ORADATA' SIZE 10m AUTOEXTEND ON NEXT 5M MAXSIZE 1024m

LOGGING

ONLINE

PERMANENT

EXTENT MANAGEMENT LOCAL UNIFORM. SIZE 5M

BLOCKSIZE 16K

SEGMENT SPACE MANAGEMENT AUTO

FLASHBACK ON

Add data files

ALTER TABLESPACE MYTBS ADD DATAFILE'+ ORADATA' SIZE 10m AUTOEXTEND OFF

If you set the initialization parameter db_create_file_dest (default is empty), you don't even need to write the disk group name, for example:

SQL > show parameter db_create_file_dest

NAME TYPE VALUE

-

Db_create_file_dest string + ORADATA

SQL > ALTER TABLESPACE MYTBS ADD DATAFILE SIZE 10m AUTOEXTEND OFF

Tablespace altered.

Tips:

For existing systems, the easiest way to move to ASM storage is to use RMAN

After the three statements have been established, view the system files:

[root@rac01 ~] # su-grid

[grid@rac01 ~] $

[grid@rac01 ~] $asmcmd

ASMCMD > ls

OCR_VOTE/

ORADATA/

ORAFLASH/

ASMCMD > cd oradata/racdb

ASMCMD > ls-l

Type Redund Striped Time Sys Name

DATAFILE UNPROT COARSE NOV 30 17:00:00 Y MYTBS.504.768590521

DATAFILE UNPROT COARSE NOV 30 17:00:00 Y MYTBS.505.768590741

DATAFILE UNPROT COARSE NOV 30 17:00:00 Y SYSAUX.261.739387301

DATAFILE UNPROT COARSE NOV 30 17:00:00 Y SYSTEM.260.739387283

DATAFILE UNPROT COARSE NOV 30 17:00:00 Y TEST.340.740166807

DATAFILE UNPROT COARSE NOV 30 17:00:00 Y TEST.341.740166937

DATAFILE UNPROT COARSE NOV 30 17:00:00 Y TONYTBS.506.768590761

DATAFILE UNPROT COARSE NOV 30 17:00:00 Y UNDOTBS1.262.739387315

DATAFILE UNPROT COARSE NOV 30 17:00:00 Y UNDOTBS2.264.739387351

DATAFILE UNPROT COARSE NOV 30 17:00:00 Y USERS.265.739387361

N mytbs01.dbf = > + ORADATA/RACDB/DATAFILE/MYTBS.504.768590521

N test01.dbf = > + ORADATA/RACDB/DATAFILE/TEST.340.740166807

N test02.dbf = > + ORADATA/RACDB/DATAFILE/TEST.341.740166937

We can see that mytbs01 specifies the path'+ ORADATA/racdb/datafile/mytbs01.dbf', so it is displayed with both mytbs01.dbf and corresponding MYTBS.504.768590521. The newly added MYTBS tablespace file only writes'+ ORADATA', and the generated file is MYTBS.505.768590741, as well as the established TONYTBS, the corresponding file is TONYTBS.506.768590761, and there is no linked file.

Modify the data file size (similar to file system operations):

ALTER DATABASE DATAFILE'+ DATA/wsjdell/datafile/users.256.754063811' RESIZE 200m

For archive directories and data file directories, another concern is the problem of space. How can we judge that disk groups need to add new disks or new disk groups to meet data growth?

ASMCMD > pwd

+ oradata/racdb/datafile

ASMCMD > du

Used_MB Mirror_used_MB

2949 2949

ASMCMD > lsdg

State Type Rebal Sector Block AU Total_MB Free_MB Req_mir_free_MB Usable_file_MB Offline_disks Voting_files

Name

MOUNTED EXTERN N 512 4096 1048576 10236 9840 0 9840 0 N OCR_VOTE/

MOUNTED EXTERN N 512 4096 1048576 10236 465 0 465 0 N ORADATA/

MOUNTED EXTERN N 512 4096 1048576 4094 3999 0 3999 0 N ORAFLASH/

[root@rac01 ~] # su-grid

[grid@rac01 ~] $sqlplus "/ as sysasm"

SQL > select name, total_mb, free_mb,cold_used_mb from v$asm_diskgroup

NAME TOTAL_MB FREE_MB COLD_USED_MB

OCR_VOTE 10236 9840 396

ORADATA 10236 465 9771

ORAFLASH 4094 3999 95

You can see that the size of free_mb (or Usable_file_MB) queried through sql statements in asmcmd and asm instances is the same.

The use of tablespaces needs to be viewed through database SQL or auxiliary tools such as Toad.

-- online log file path ONLINELOG

ASMCMD > pwd

+ oradata/racdb

ASMCMD > ls-l

Type Redund Striped Time Sys Name

Y ARCHIVELOG/

Y CONTROLFILE/

Y DATAFILE/

Y ONLINELOG/

Y PARAMETERFILE/

Y TEMPFILE/

N arch/

N control01.ctl = > + ORADATA/RACDB/CONTROLFILE/Current.256.739387263

N control02.ctl = > + ORADATA/RACDB/CONTROLFILE/Current.257.739387265

N redo01.log = > + ORADATA/RACDB/ONLINELOG/group_1.258.739387273

N redo02.log = > + ORADATA/RACDB/ONLINELOG/group_2.259.739387281

N redo03.log = > + ORADATA/RACDB/ONLINELOG/group_3.266.739393547

N redo04.log = > + ORADATA/RACDB/ONLINELOG/group_4.267.739393547

N spfileracdb.ora = > + ORADATA/RACDB/PARAMETERFILE/spfile.268.739393555

ASMCMD > cd onlinelog

ASMCMD > ls-l

Type Redund Striped Time Sys Name

ONLINELOG UNPROT COARSE NOV 30 17:00:00 Y group_1.258.739387273

ONLINELOG UNPROT COARSE NOV 30 17:00:00 Y group_2.259.739387281

ONLINELOG UNPROT COARSE NOV 30 17:00:00 Y group_3.266.739393547

ONLINELOG UNPROT COARSE NOV 30 17:00:00 Y group_4.267.739393547

Like other key files, the directory + oradata/racdb is manually specified when building the library, so after all

Easily recognizable names such as redo01.log, redo02.log, etc., all exist in the form of link names.

Redo logfile redundancy settings can be set on different disk groups, such as ORADATA and ORAFLASH.

Join a redundancy group in the same way as in a file system (the only difference is that you cannot add parentheses to a file, if only one member is added).

Alter database add logfile member'+ ORAFLASH' to group 1

Alter database add logfile member'+ ORAFLASH' to group 2

Alter database add logfile member'+ ORAFLASH' to group 3

Alter database add logfile member'+ ORAFLASH' to group 4

After joining, you can see 2 members of each group by querying v$logfile.

ASMCMD > cd + oraflash

ASMCMD > ls

RACDB/

ASMCMD > cd racdb

ASMCMD > ls

ONLINELOG/

ASMCMD > ls-l

Type Redund Striped Time Sys Name

ONLINELOG UNPROT COARSE NOV 30 20:00:00 Y group_1.256.768602255

ONLINELOG UNPROT COARSE NOV 30 21:00:00 Y group_2.257.768603599

ONLINELOG UNPROT COARSE NOV 30 21:00:00 Y group_3.258.768603683

ONLINELOG UNPROT COARSE NOV 30 21:00:00 Y group_4.259.768603705

Join a redo log group.

Alter database add logfile group 5 ('+ ORADATA','+ ORAFLASH') size 50m

SQL > select member from v$logfile

MEMBER

-

+ ORADATA/racdb/redo01.log

+ ORADATA/racdb/redo02.log

+ ORADATA/racdb/redo03.log

+ ORADATA/racdb/redo04.log

+ ORAFLASH/racdb/onlinelog/group_1.256.768602255

+ ORAFLASH/racdb/onlinelog/group_2.257.768603599

+ ORAFLASH/racdb/onlinelog/group_3.258.768603683

+ ORAFLASH/racdb/onlinelog/group_4.259.768603705

+ ORADATA/racdb/onlinelog/group_5.508.768604159

+ ORAFLASH/racdb/onlinelog/group_5.260.768604161

10 rows selected.

SQL >

-- Parameter file path PARAMETERFILE (DB parameter file, non-ASM instance parameter file)

ASMCMD > pwd

+ oradata/racdb/parameterfile

ASMCMD > ls-l

Type Redund Striped Time Sys Name

PARAMETERFILE UNPROT COARSE NOV 30 17:00:00 Y spfile.268.739393555

ASMCMD >

-- temporary file path TEMPFILE

ASMCMD > cd tempfile

ASMCMD > ls-l

Type Redund Striped Time Sys Name

TEMPFILE UNPROT COARSE NOV 30 17:00:00 Y TEMP.263.739387321

3. Expand the disk group size

ASMCMD > lsdg

State Type Rebal Sector Block AU Total_MB Free_MB Req_mir_free_MB Usable_file_MB Offline_disks Voting_files

Name

MOUNTED EXTERN N 512 4096 1048576 10236 9840 0 9840 0 N OCR_VOTE/

MOUNTED EXTERN N 512 4096 1048576 10236 414 0 414 0 N ORADATA/

MOUNTED EXTERN N 512 4096 1048576 4094 3737 0 3737 0 N ORAFLASH/

Through the lsdg or v$asm_diskgroup view, we find that there may not be enough disk group space, so should we join a new disk group or add a new disk based on the original disk group?

In order to get better Iamp O performance, it is common to add new disks to the disk group. ASM disk groups support dynamic expansion. We can dynamically add new disks to the existing disk groups. After the new disks are added, Oracle Rebalance through the background RBAL to balance the current data to the newly added disks. Drop disks also Rebalance.

The asm_power_limit parameter is used to control the speed of Rebalance. A value of 1: 11 rebalance power indicates that the greater the number of process RBAL of the started rebalance, the faster the balance speed. The default value is 1. However, the higher the number, the performance may be affected by Rebalance, which is generally set to between 3 and 6 for balance.

After adding the new disk, assume that / dev/sde, / dev/sdf, fdisk is partitioned as / dev/sde1, / dev/sdf1.

[grid@rac01 ~] $sqlplus "/ as sysasm"

SQL*Plus: Release 11.2.0.1.0 Production on Wed Nov 30 23:04:08 2011

Copyright (c) 1982, 2009, Oracle. All rights reserved.

Connected to:

Oracle Database 11g Enterprise Edition Release 11.2.0.1.0-Production

With the Real Application Clusters and Automatic Storage Management options

SQL > show parameter asm_power_limit

NAME TYPE VALUE

-

Asm_power_limit integer 1

SQL > alter system set asm_power_limit=5;-- modify the power value.

System altered.

Or use the

ALTER DISKGROUP diskgroupname REBALANCE POWER 5

-- check existing disks.

SQL > select group_number, name from v$asm_disk order by 1

GROUP_NUMBER NAME

0

1 OCR_VOTE01

2 ASMDATA01

3 ASMDATA02

-- View existing disk groups.

SQL > select group_number, name from v$asm_diskgroup order by 1

GROUP_NUMBER NAME

1 OCR_VOTE

2 ORADATA

3 ORAFLASH

Create a new disk:

[root@rac01] # / usr/sbin/oracleasm createdisk ASMDATA03 / dev/sde1

Writing disk header: done

Instantiating disk: done

[root@rac01 ~] # / usr/sbin/oracleasm listdisks

ASMDATA01

ASMDATA02

ASMDATA03

OCR_VOTE01

On other nodes:

[root@rac02 ~] # / usr/sbin/oracleasm scandisks

Reloading disk partitions: done

Cleaning any stale ASM disks...

Scanning system for ASM disks...

[root@rac02 ~] # / usr/sbin/oracleasm listdisks

ASMDATA01

ASMDATA02

ASMDATA03

OCR_VOTE01

The new disk ASMDATA03 needs to be added to the ORADATA disk group:

[grid@rac01 ~] $sqlplus "/ as sysasm"

SQL > ALTER DISKGROUP ORADATA ADD DISK 'ORCL:ASMDATA03'

Diskgroup altered.

Or (you need to specify ASM_DISKSTRING ='/ dev/*' in the initial parameter)

SQL > ALTER DISKGROUP ORADATA ADD DISK'/ dev/sde1' name ASMDATA03

The speed is still very fast (probably not much data needs to be transferred from disk to disk). You can find some large test libraries to test the speed and performance of different power values. After notice, change the asm_power_limit value to the default value of 1. 0.

SQL > alter system set asm_power_limit=1

System altered.

-

Note that if the expanded disk group is Normal Redundant, then failure group.

The statements related to modifying and adding a disk group are similar (you need to set the initial parameter ASM_DISKSTRING='/dev/*'):

Specific reference:

Http://docs.oracle.com/cd/E11882_01/server.112/e18951/asmdiskgrps.htm#CHDHHABI

One disk is composed of failgroup (Normal):

ALTER DISKGROUP dgroup1 NORMAL REDUNDANCY

FAILGROUP fg1 DISK'/ dev/sde1' NAME ASMDATA05

FAILGROUP fg2 DISK'/ dev/sdf1' NAME ASMDATA06

One disk is composed of failgroup (High):

Create diskgroup data2 high redundancy

Failgroup fg1 disk'/ dev/raw/raw3' name D2a

Failgroup fg2 disk'/ dev/raw/raw4' name D2B

Failgroup fg3 disk'/ dev/raw/raw5' name D2C

Multiple disks make up failgroup (Normal):

CREATE DISKGROUP dgroup1 NORMAL REDUNDANCY

FAILGROUP controller1 DISK

'/ dev/diska1'

'/ dev/diska2'

'/ dev/diska3'

'/ dev/diska4'

FAILGROUP controller2 DISK

'/ dev/diskb1'

'/ dev/diskb2'

'/ dev/diskb3'

'/ dev/diskb4'

Syntax:

CREATE DISKGROUP diskgroup_name

[{HIGH | NORMAL | EXTERNAL} REDUNDANCY]

[FAILGROUP failgroup_name]

DISK [NAME disk_name] [SIZE size_clause] [FORCE | NOFORCE]...

You can see what is going on through the v$asm_operation view.

Here are a few points to pay attention to:

(1) first of all, sqlplus login requires sysasm role, because sysdba can only be viewed and cannot be modified.

(2) the disk information followed by add disk is' ORCL:XXX', and XXX is the ASM disk label seen by listdisks.

If it's just add disk 'XXX', it will make a mistake.

(3) similarly, it is not possible to write'/ dev/sde1' directly after add disk, and permission errors will be reported.

View the disk group space expansion through asmcmd:

[root@rac02 ~] # su-grid

[grid@rac02 ~] $

[grid@rac02 ~] $asmcmd

ASMCMD > lsdg

State Type Rebal Sector Block AU Total_MB Free_MB Req_mir_free_MB Usable_file_MB Offline_disks Voting_files

Name

MOUNTED EXTERN N 512 4096 1048576 10236 9840 0 9840 0 N OCR_VOTE/

MOUNTED EXTERN Y 512 4096 1048576 30709 20694 0 20694 0 N ORADATA/

MOUNTED EXTERN N 512 4096 1048576 4094 3737 0 3737 0 N ORAFLASH/

ASMCMD >

You can see that the Total_MB of the ORADATA disk group has changed to 30g (30709m), obviously

Successfully joined 20g / dev/sde1.

Delete the disks in the disk group (you also need to set the power value to speed up RBAL):

SQL > ALTER DISKGROUP ORADATA DROP DISK 'ASMDATA03'

Diskgroup altered.

If you check it immediately after execution, the size of the ORADATA disk group may not change. You need to look at the v$asm_operation view to see what is going on, and then change it. The results of not waiting and waiting for 3 minutes after executing the drop command are as follows:

ASMCMD > lsdg-check it right away (no change in size)

State Type Rebal Sector Block AU Total_MB Free_MB Req_mir_free_MB Usable_file_MB Offline_disks Voting_files

Name

MOUNTED EXTERN N 512 4096 1048576 10236 9840 0 9840 0 N OCR_VOTE/

MOUNTED EXTERN Y 512 4096 1048576 30709 20694 0 20694 0 N ORADATA/

MOUNTED EXTERN N 512 4096 1048576 4094 3737 0 3737 0 N ORAFLASH/

ASMCMD >

ASMCMD > lsdg-wait for 3 minutes to check (of course, the waiting time is longer if the amount of data is large)

State Type Rebal Sector Block AU Total_MB Free_MB Req_mir_free_MB Usable_file_MB Offline_disks Voting_files

Name

MOUNTED EXTERN N 512 4096 1048576 10236 9840 0 9840 0 N OCR_VOTE/

MOUNTED EXTERN N 512 4096 1048576 10236 223 0 223 0 N ORADATA/

MOUNTED EXTERN N 512 4096 1048576 4094 3737 0 3737 0 N ORAFLASH/

You can see that the total_mb of ORADATA has changed back to 10G.

If you want the ALTER DISKGROUP statement to complete all the work before returning to user control, you can attach the REBALANCE WAIT clause during execution, so that the statement will wait for the automatic balancing operation, and directly all the operations will be completed before returning the result. Of course, during the waiting period, if you change your mind and do not want to continue to wait, CTRL+C will be interrupted to gain control. At this time, the balancing operation will not be affected and will continue in the background.

ASMCMD > lsdsk-- ASMDATA03 disk disappears.

Path

ORCL:ASMDATA01

ORCL:ASMDATA02

ORCL:OCR_VOTE01

Note that DROP DISK simply removes ASMDATA03 from the disk group:

[root@rac02 ~] # / usr/sbin/oracleasm listdisks

ASMDATA01

ASMDATA02

ASMDATA03

OCR_VOTE01

Note:

(1), or you can only set rebalance power for a certain diskgroup, such as:

Alter diskgroup ORADATA rebalance power 8

(2), or set it in the command

Alter diskgroup ORADATA add disk 'ORCL:ASMDATA03' rebalance power 8

Alter diskgroup ORADATA drop disk 'ASMDATA03' rebalance power 8

It is important to note that both add and drop need to wait some time before doing actions for this disk or disk group, otherwise an error may be reported, or watch the v$asm_operation to view the transaction.

As follows:

SQL > select * from v$asm_operation

GROUP_NUMBER OPERA STAT POWER ACTUAL SOFAR EST_WORK EST_RATE

EST_MINUTES ERROR_CODE

-

2 REBAL RUN 8 8 173 6680 741

View it again at regular intervals (until the related transaction disappears from this view):

SQL > select * from v$asm_operation

No rows selected

Due to the ASM auto-balancing feature mentioned earlier, the return of the above statement does not mean that the disk has been deleted. At this time, the backend may be busy performing IO rebalancing work, so if DBA suddenly realizes the operation error at this time, but the disk does not need to be deleted, you can also cancel the deletion operation immediately through the alter diskgroup dgname undrop disks statement, for example:

SQL > alter diskgroup ORADATA undrop disks

Diskgroup altered.

As long as the delete operation is not really completed, the task will be cancelled, otherwise, the above statement will not save anything. If you want to save it, DBA can only add the disk back to the disk group through the ADD statement.

4. Add a new disk group

-- check existing disks.

SQL > select group_number, name from v$asm_disk order by 1

GROUP_NUMBER NAME

1 OCR_VOTE01

2 ASMDATA01

2 ASMDATA03

3 ASMDATA02

-- View existing disk groups.

SQL > select group_number, name from v$asm_diskgroup order by 1

GROUP_NUMBER NAME

1 OCR_VOTE

2 ORADATA

3 ORAFLASH

Create a new disk (/ dev/sdf1):

[root@rac01] # / usr/sbin/oracleasm createdisk ASMDATA04 / dev/sdf1

Writing disk header: done

Instantiating disk: done

[root@rac01 ~] # / usr/sbin/oracleasm listdisks

ASMDATA01

ASMDATA02

ASMDATA03

ASMDATA04

OCR_VOTE01

On other nodes:

[root@rac02 ~] # / usr/sbin/oracleasm scandisks

Reloading disk partitions: done

Cleaning any stale ASM disks...

Scanning system for ASM disks...

Instantiating disk "ASMDATA04"

[root@rac02 ~] # / usr/sbin/oracleasm listdisks

ASMDATA01

ASMDATA02

ASMDATA03

ASMDATA04

OCR_VOTE01

Start setting up the disk group (here is the external mode, specific syntax reference documentation):

Create a new disk group on node 1:

SQL > CREATE DISKGROUP ORAINDX EXTERNAL REDUNDANCY

DISK 'ORCL:ASMDATA04'

SQL > select group_number, name from v$asm_diskgroup

GROUP_NUMBER NAME

1 OCR_VOTE

2 ORADATA

3 ORAFLASH

4 ORAINDX

ASMCMD > lsdg

State Type Rebal Sector Block AU Total_MB Free_MB Req_mir_free_MB Usable_file_MB Offline_disks Voting_files

Name

MOUNTED EXTERN N 512 4096 1048576 10236 9840 0 9840 0 N OCR_VOTE/

MOUNTED EXTERN N 512 4096 1048576 30709 20694 0 20694 0 N ORADATA/

MOUNTED EXTERN N 512 4096 1048576 4094 3737 0 3737 0 N ORAFLASH/

MOUNTED EXTERN N 512 4096 1048576 10236 10186 0 10186 0 N ORAINDX/

You can see that it all works on Node 1. But other nodes do not take effect (lsdg and lsdsk can't see it)

The new disk group needs to be mounted manually.

SQL > ALTER DISKGROUP ORAINDX MOUNT

Diskgroup altered.

You can see it by looking at it on other nodes:

SQL > select name from v$asm_diskgroup

SQL > select name from v$asm_disk

ASMCMD > lsdsk

ASMCMD > lsdg

5, delete the disk group

Syntax: drop diskgroup gpname, if the deleted diskgroup is not empty, executing the above statement directly will report an error. At this time, you can automatically delete the files contained in the disk group by attaching the including contents clause. Deleting a disk group automatically modifies the value of the ASM_DISKGROUPS initialization parameter in spfile (if SPFILE is used).

-- Tips:

If a file is deleted, its associated alias (Alias) will also be deleted automatically.

SQL > alter diskgroup asmdisk2 drop file'+ ASMDISK2/repdb/datafile/temp01.dbf'

Diskgroup altered.

Second, ASM instances are relevant.

1. Permissions and roles related to ASM

Common users and groups when installing Grid Infrastructure:

Grid Infrastructure operating system user grid, the primary group is oinstall, and the secondary group is asmadmin, asmdba, asmoper

Oracle RAC operating system user oracle, the primary group is oinstall, and the secondary group is dba, oper, asmdba

Oracle in 11 g release2 recommends managing Grid Infrastructure and ASM instances independently.

OSASM (asmadmin) user group

If we use ASM, we must create an osasm (asmadmin) user group whose members will be assigned

SYSASM permissions to meet the permission requirements of group members to manage Oracle Clusterware and ASM.

OSDBA for ASM group (asmdba) user group

Members of the OSDBA (asmdba) user group will be given read and write access to the ASM file. GI/CRS owners, users and

All oracle database software owners must be members of the group. All members of the OSDBA (dba) user group must also be members of the asmdba group.

OSOPER for ASM (asmoper) user group

Asmoper and osoper are similar to additional optional user groups that can be created to satisfy the

The user has a set of restricted ASM instance management rights (the SYSOPER role of ASM), which include starting and stopping ASM instances

By default, members of the OSASM (asmadmin) group will have ASM administrative rights for all SYSOPER.

Grid users install clusters separately, such as asm instances, listening resources, node resources, etc.

Oracle users only install oracle code

# groupadd oinstall

# groupadd asmadmin

# groupadd asmdba

# groupadd asmoper

# groupadd dba

# groupadd oper

# useradd-g oinstall-G asmadmin,asmdba,asmoper grid

# useradd-g oinstall-G dba, oper, asmdba oracle

For the meaning of the specific representative, refer to:

Http://www.oracledatabase12g.com/archives/oracle-installation-os-user-groups.html

User group description of the user group to which the user group belongs

Oinstall grid, oracle Oracle Inventory and Software Owner

Dba oracle Database Administrator

Asmadmin grid Oracle ASM Group

Asmdba grid, oracle ASM Database Administrator Group

Asmoper grid ASM Operator Group

Oper oracle Database Operator

If no asmdba group is assigned to oracle users, it will cause oracle users to fail to recognize diskgroup

Failed to start the corresponding node instance.

Remarks:

Sysdba is still used in Oracle10g to manage asm instances, and a new role, sysasm, is used in Oracle11g, dedicated to

Managing asm is equivalent to the sysdba role for asm instances. After logging in as a grid user in Oracle11g RAC, with

Sysdba login can also view the status related to asm instances, but no changes can be made until the sysasm roles are connected.

Sure.

2. ASM instance

ASM instances are similar to ORACLE database instances and are composed of SGA and background processes. The difference is that

Oracle instances manage databases, while asm instances manage only ASM disk groups. Here grid users belong to

Asmadmin group, used to manage ASM

[root@rac01 ~] # su-grid

[grid@rac01 ~] $id

Uid=501 (grid) gid=501 (oinstall) groups=501 (oinstall), 504,506 (asmdba), 507 (asmoper)

[grid@rac01 ~] $export ORACLE_SID=+ASM1 (generally not used, because there is only one ASM instance under grid users)

[grid@rac01 ~] $env | grep ORA

ORA_NLS11=/u01/grid/11.2.0/nls/data

ORACLE_SID=+ASM1

ORACLE_BASE=/u01/grid/crs

ORACLE_TERM=vt100

ORACLE_HOME=/u01/grid/11.2.0

[grid@rac01 ~] $sqlplus / as sysasm

SQL*Plus: Release 11.2.0.1.0 Production on Sat Dec 3 07:13:39 2011

Copyright (c) 1982, 2009, Oracle. All rights reserved.

Connected to:

Oracle Database 11g Enterprise Edition Release 11.2.0.1.0-Production

With the Real Application Clusters and Automatic Storage Management options

SQL > show parameter instance_name

NAME TYPE VALUE

-

Instance_name string + ASM1

As a grid user, connect to the ASM instance and use both sysdba and sysasm roles

Login with sysdba can also view the status related to asm instances, but no changes can be made.

It is not possible until the sysasm role is connected.

A. enable and close ASM instances

Similarly, ASM instances can also be startup nomount / mount / open / force.

Nomount: just start the instance

Mount / open: start instances and load disk groups, open is the same as mount

Force: execute shutdown abort first, then startup

Test:

[grid@rac01 ~] $sqlplus / as sysasm

SQL > startup nomount

ASM instance started

Total System Global Area 120023424 bytes

Fixed Size 2082208 bytes

Variable Size 102775392 bytes

ASM Cache 25165824 bytes

SQL > select name,state from v$asm_diskgroup

NAME STATE

ASMDISK1 DISMOUNTED

ASMDISK2 DISMOUNTED

SQL > select instance_name,status from v$instance

INSTANCE_NAME STATUS

--

+ ASM1 STARTED

Then load the disk group, note that it is not alter database:

SQL > alter diskgroup all mount

Diskgroup altered.

SQL > select name,state from v$asm_diskgroup

NAME STATE

ASMDISK1 MOUNTED

ASMDISK2 MOUNTED

Close the ASM instance: several options for NORMAL/IMMEDIATE/TRANSACTIONAL/ABORT

Just like shutting down a normal database instance:

SQL > shutdown immediate

ASM diskgroups dismounted

ASM instance shutdown

B. initialization parameters of ASM instance

ASM initialization is also divided into spfile and pfile, and the operation is the same. Compared with RDBMS database, there are still some differences.

Parameters.

SQL > create pfile='/tmp/asminit.ora' from spfile

File created.

Because the memory footprint of ASM instances is very small, 100 megabytes of memory is basically enough, not to mention memory correlation.

INSTANCE_TYPE: the value is ASM in ASM and RDBMS in the database instance.

ASM_POWER_LIMIT: specifies the degree of disk rebalance, which has a level of 0-11. The default value is 1. Specify

The higher the level, the faster the operation of the rebalance will be completed (which means, of course, that the

Take up more resources), if you specify a lower level, although the rebalance operation will take longer, for the current

The IO and load impact of the system will be less, and the intermediate degree needs to be measured by DBA according to the actual situation. In addition, this reference

The number specifies only a default value, which can be modified dynamically or on the statement-level command line during the operation.

Power is specified, overriding the default value.

ASM_DISKSTRING: in the simplest terms, set the disk to check when ASM starts. This option can

Multiple values are specified at the same time and wildcards are supported. For example, if you only check the devices under / dev/dsk/, you can set

The parameter is as follows: / dev/dsk/*,. By default, this parameter is empty. If it is empty, it means that ASM will find the system.

All devices in the ASM that have read and write permissions.

ASM_DISKGROUPS: specifies the magnetic to be loaded when the instance is started or when the alter diskgroup all mount statement is started

The disk group, if empty, will actually only boot to the NOMOUNT state. If you are using SPFILE

This parameter generally does not need to be modified manually, and ASM can automatically update the values in the initialization parameter.

[grid@rac01 tmp] $sqlplus / as sysasm

SQL*Plus: Release 11.2.0.1.0 Production on Tue Nov 29 05:24:38 2011

Copyright (c) 1982, 2009, Oracle. All rights reserved.

Connected to:

Oracle Database 11g Enterprise Edition Release 11.2.0.1.0-Production

With the Real Application Clusters and Automatic Storage Management options

SQL > show parameter

NAME TYPE VALUE

-

Asm_diskgroups string ORADATA, ORAFLASH

Asm_diskstring string

Asm_power_limit integer 1

.

3. ASM related views

[root@rac01 ~] # su-oracle

[oracle@rac01 ~] $sqlplus "/ as sysdba"

SQL > select TABLE_NAME from dict where table_name like 'VIP ASM%'

TABLE_NAME

-

V$ASM_ACFSSNAPSHOTS

V$ASM_ACFSVOLUMES

V$ASM_ALIAS-record file alias

V$ASM_ATTRIBUTE-record the properties of the ASM disk group

V$ASM_CLIENT-the client instance information of the current connection

V$ASM_DISK-disk and disk group information managed by ASM

V$ASM_DISKGROUP-- ASM disk group

V$ASM_DISKGROUP_STAT-ASM disk group status, size

V$ASM_DISK_IOSTAT-- ASM disk group iBandO statu

V$ASM_DISK_STAT

V$ASM_FILE

TABLE_NAME

-

V$ASM_FILESYSTEM

V$ASM_OPERATION-the operation information of the current disk

V$ASM_TEMPLATE

V$ASM_USER

V$ASM_USERGROUP

V$ASM_USERGROUP_MEMBER

V$ASM_VOLUME

V$ASM_VOLUME_STAT

19 rows selected.

4. ASM architecture

ASM instance:

1) RBAL: rebalancer process, which is responsible for planning Reblance activities for ASM disk groups

2) ABRn: a child process of the RBAL process that actually completes Reblance activities

RDBMS instance:

1) RBAL: responsible for opening all disks for each disk group

2) ASMB: this process acts as an information channel between the ASM instance and the database instance. This process is responsible for working with

The communication of the ASM instance, which first uses Diskgroup name to obtain the ASM instance that manages the Diskgroup from CSS

Connect the string, and then establish a persistent connection to the ASM through which the two instances exchange information periodically, and at the same time

It's a heartbeat mechanism.

3) O0nn 01-10: this group of processes establishes connections to ASM instances, and some long-term operations such as creating data files

RDBMS sends messages to ASM through these processes

Interaction between ASM Instance and RDBMS

When a disk group is mounted on an ASM instance, ASM will send Disk Group Name and ASM Instance Name

Information such as Oracle Home Path is registered with CSS (Cluster Sychronization Service), and it will be used

To construct Connect String. When you need to access an ASM File during RDBMS startup, RDBMS will

Contact CSS, get the Connect String from CSS, and then initiate a connection to the ASM instance

The initial connection between the ASM and the RDBMS instance is called Umbilicu (umbilical cord), as long as RDBMS opens ASM File

The connection will remain active. This connection is not available until all ASM File is closed by the RDBMS instance.

It will be closed.

According to the understanding of ASM, ASM actually means that LVM puts on the vest of Oracle, Disk corresponds to PV and Diskgroup corresponds to VG.

5. ASM efficient storage technology

Automatic storage management provides vertical integration of file systems and volume managers directly in the Oracle kernel

This brings the advantages of the "virtualization" type provided by the San system (easy to manage, higher availability)

And specially used for Oracle database files. ASM provides a quick way to configure the database to achieve optimal performance

And resource utilization. It automatically manages database files and their placement through the Oracle kernel, eliminating the need for

Third-party file systems and volume managers manage Oracle files. ASM eliminates the time-consuming manual I _ peg O performance and tuning

The whole task greatly saves DBA time.

ASM mirroring (mirroring) and striping (striping): ASM divides files into 1MB-sized regions (extent, AU)

And distribute the extents of all files evenly among all the disks of the disk group. ASM does not use mathematical functions to track the

Place, and use the pointer to record the location of the area. In this way, ASM can move a text when the disk group configuration changes

Without having to move all areas according to the formula and according to the number of disks. For files that require low latency

(for example, log files), ASM provides fine-grained (128k) segmentation to be separated by multiple disks in parallel and to handle more

Large I _ paw O. ASM distributes the Icano load among all available resources, eliminating the need for manual Icano regulation (by dividing the

Scatter database files to avoid hot spots) while optimizing performance.

ASM mirroring is more flexible than operating system disk mirroring because ASM can set redundancy levels based on files

That is, two files in the same disk group can be mirrored while the other is not mirrored. ASM mirror

Like it happened at the district level.

ASM's dynamic storage configuration: ASM makes it possible to adjust the storage configuration online, that is, it helps DBA manage

A dynamic database environment that allows DBA to expand or reduce the size of the database without shutting down the database

To adjust the storage configuration. After adding disks to or removing disks from a disk group, ASM will automatically

Rebalance-redistributes file data evenly across all disks in the disk group.

Third, ASM disk redundancy and fault handling

The disk redundancy strategy of ASM can be divided into three categories: external redundancy, standard redundancy and high redundancy.

External redundancy does not require failure disk groups, and standard and high redundancy must have failure disk groups

For example, for standard redundancy (Normal Redundancy), ASM requires that the disk group have at least

Two failure disk groups that provide double mirror protection for the same data (mirrored units in ASM)

Not a disk, nor a block, but a unit of AU, the default size of which is 1m) there will be two masters and slaves

Mirror images, and ASM automatically ensures that master and slave images do not exist in the same failure magnetic field through algorithms.

Disk group, which ensures that even if the entire failure disk group is damaged, the data will not be lost. As for Gao

Degree redundancy (High Redundancy) is even more secure, which requires at least three failure disk groups, that is,

It is a mirror image of AU with one master and more slaves, which will be more secure in theory.

If the disk is damaged, the damaged disk is automatically offline and drop by default, but the

The disk group in which the disk belongs will remain in MOUNT state. If the disk is mirrored, the application will not have

As a result, the mirror disk will automatically take over (as long as not all failure disk groups are damaged), otherwise

The disk group will automatically DISMOUNT. For example, a standard redundant failure group has 6 disks (corresponding to 6 bare settings)

If a disk is broken at this time, it doesn't matter, the operation continues, the broken piece will be automatically dropped, and the rest

The next 5 disks can still afford normal read and write operations.

ASM scalability:

Up to 63 disk groups are supported

Supports up to 10000 disk

Maximum support for 4pb/ disk

Supports up to 40 exabyte/ASM Stora

Supports up to 100 W files / disk groups

Maximum 35tb of a single file in external redundancy, maximum 5.8tb of a single file in standard redundancy, and single in high redundancy

The maximum 3.9tb of the file.

Load and unload disk groups

If you use UMOUNT disk groups, be sure to operate carefully and make sure that what is saved in UNMOUNT disk groups

The database corresponding to the file is not currently started, and this operation will directly cause the database SHUTDOWN.

Only the disk groups of mount can be used by the database and perform add/drop operations. Disk groups in ASM are default.

Recognition is automatically loaded when the ASM instance starts.

SQL > select group_number,name,state,total_mb,free_mb from v$asm_diskgroup

GROUP_NUMBER NAME STATE TOTAL_MB FREE_MB

1 ASMDATA1 MOUNTED 20472 18667

2 ASMDATA2 MOUNTED 16378 14621

Set the ASMDATA2 disk group UNMOUNT:

SQL > alter diskgroup ASMDATA2 dismount

Diskgroup altered.

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

GROUP_NUMBER NAME STATE

1 ASMDATA1 MOUNTED

0 ASMDATA2 DISMOUNTED

SQL > alter diskgroup ASMDATA2 mount;-- mount again.

Diskgroup altered.

Fourth, the related commands of ASM under Linux ORACLEASM, ASMCMD, ASMCA

1. ORACLEASM command

After installing asm lib, we can view the relevant commands through man:

[grid@rac01 tmp] $man oracleasm

Use ASMLib to create an ASM Disks with the following syntax:

# / usr/sbin/oracleasm createdisk disk_name device_partition_name

Disk_name is a name you choose for ASM Disk, which can only contain numbers, letters and underscores, such as OCR01, DATA01, etc. The partition of the system disk labeled ASM by device_partition_name, as shown in

/ dev/sdb1, / dev/sdc1, etc.

If you find that you have set up the wrong disk or need unmark, you can run the following command:

# / usr/sbin/oracleasm deletedisk disk_name

Set up shared disks.

# / usr/sbin/oracleasm createdisk OCR_VOTE01 / dev/sdb1

# / usr/sbin/oracleasm createdisk ASM_DATA01 / dev/sdc1

Use the listdisks command to confirm their availability.

[root@rac001 ~] # / usr/sbin/oracleasm listdisks

ASM_DATA01

ASM_DATA02

ASM_FRA

OCR_VOTE01

As the root user on all other nodes, use the scandisks command to scan the ASM disks that have been created, that is, we only need to create ASM disks on node 1, not on the other nodes.

[root@rac002 ~] # / usr/sbin/oracleasm scandisks

Reloading disk partitions: done

Cleaning any stale ASM disks...

Scanning system for ASM disks...

Instantiating disk "OCR_VOTE01"

Instantiating disk "ASM_DATA01"

Instantiating disk "ASM_DATA02"

Instantiating disk "ASM_FRA"

Finally, check the availability of the ASM disk through listdisks at other nodes.

[root@rac002 ~] # / usr/sbin/oracleasm listdisks

ASM_DATA01

ASM_DATA02

ASM_FRA

OCR_VOTE01

2. ASMCMD command

[root@rac01 ~] # su-grid

[grid@rac01 ~] $id

Uid=501 (grid) gid=501 (oinstall) groups=501 (oinstall), 504,506 (asmdba), 507 (asmoper)

[grid@rac01 ~] $asmcmd

ASMCMD >

If asm-p enters, it will bring a path (path)

[grid@rac01] $asmcmd-p

ASMCMD [+] > cd oradata

ASMCMD [+ oradata] >

Get help help [command]:

ASMCMD [+ oradata] > help du

Du [- H] [dir]

Display total space used for files located recursively under [dir]

Similar to "du-s" under UNIX; default is the current directory. Two

Values are returned, both in units of megabytes. The first value does

Not take into account mirroring of the diskgroup while the second does.

For instance, if a file occupies 100 MB of space, then it actually

Takes up 200 MB of space on a normal redundancy diskgroup and 300 MB

Of space on a high redundancy diskgroup.

[dir] can also contain wildcards.

The-H flag suppresses the column headers from the output.

ASMCMD [+ oradata] >

3. ASMCA command

Run ASMCA to create a disk group.

Start the ASMCA configuration disk group with the login of the grid user. Because it is a graphical interface, we use the vnc session of the grid user (if the vnc of root enters su to grid, an error will be reported).

[grid@rac001 bin] $pwd

/ u01/grid/11.2.0/bin

[grid@rac001 bin] $. / asmca

The graphical interface is displayed to Disk Groups. We can see that the previously configured OCR_VOTE is already listed. Click create below to create ASM disk groups for datafile and flash recovery area.

Disk group name ORADATA, redundant section select External, click disk is ORCL:ASMDATA01, click OK. Continue create

Disk group name ORAFLASH, redundant section select External, disk is ORCL:ASMDATA02, click OK.

After all OK, click QUIT to exit.

4. ASMLib and other common commands

ORCL keyword description: discovery string of Linux ASMLib

ASMLib uses the discovery string to determine which disks ASM is requesting. A normal Linux ASMLib uses a glob string. The string must be prefixed with "ORCL:". The disk is specified by name. You can find a disk created with the name "VOL1" by discovering the string "ORCL:VOL1" in ASM. Similarly, you can query all disks that start with the string "VOL" with the discovery string "ORCL:VOL*".

The disk cannot be found with the path name in the discovery string. If the prefix is missing, the average Linux ASMLib will completely ignore the discovery string and think that it is suitable for a different ASMLib. The only exception is an empty string

It is considered to be a full wildcard. This is exactly equivalent to discovering the string "ORCL:*".

Other common commands:

SQL > create diskgroup dg2 external redundancy disk 'ORCL:VOL3'

SQL > drop diskgroup dg2 including contents; can delete the diskgroup of empty by default. If the disk group is not empty, an error will be reported if it is not connected to including contents. Specifying including contents deletes all files in the disk group, even if it is not empty.

SQL > alter diskgroup dg1 add disk 'ORCL:VOL3'

Diskgroup altered.

SQL > alter diskgroup dg1 rebalance power 8

Diskgroup altered.

SQL > alter diskgroup dg1 check all;-- check the consistency inside the ASM disk group

Diskgroup altered.

SQL > alter diskgroup dg1 check all repair;-- check and notify ASM to fix errors

Diskgroup altered.

5. Migration and file transfer / copy between ASM and file system

A, file transfer or copy

Files under ASM and OS file systems under 10g cannot be copied from each other.

11g from ASM to file system or file system to ASM is very convenient.

ASMCMD > cp spfileracdb.ora / tmp

Copying + oradata/racdb/spfileracdb.ora-> / tmp/spfileracdb.ora

[root@rac01 tmp] # ls-al spfileracdb.ora

-rw-r- 1 grid oinstall 4096 Dec 4 06:05 spfileracdb.ora

If you need to copy files under 10g, you can do the following:

Rman

Dbms_file_transfer

b. Use RMAN for migration.

At this point, the study on "what are the management and maintenance methods of ASM under Oracle11g RAC" is over. I hope to be able to solve your doubts. The collocation of theory and practice can better help you learn, go and try it! If you want to continue to learn more related knowledge, please continue to follow the website, the editor will continue to work hard to bring you more practical articles!

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