Skip to main content

Altering ASM Disk Groups


<<Back to Oracle ASM Main Page

Alter Diskgroup

There are many occasions where one need to alter the Diskgroup. In this post I will show you only those which are most frequently required. You can alter a disk group with SQL*Plus, ASMCA, or ASMCMD commands.
  • Adding Disks to a Disk Group
  • Dropping Disks from Disk Group
  • Replacing Disks in Disk Group
  • Renaming Disks in Disk Group
  • Resizing Disks in Disk Group
  • Changing Diskgroup Attributes
  • Undropping Disks in Disk Group
  • Creating ADVM Volumes

How to Add Disk in a Diskgroup

I have already created a DG "TEST_DG" Click Here to See How to Create ASM Diskgroup. The Diskgroup Configuration for TEST_DG is shown below
Let us find the available which we can add to TEST_DG diskgroup
$ asmcmd lsdsk --candidate -p
Group_Num  Disk_Num      Incarn  Mount_Stat  Header_Stat  Mode_Stat  State   Path
        0         0           0  CLOSED      PROVISIONED  ONLINE     NORMAL  AFD:TEST08
        0         1           0  CLOSED      PROVISIONED  ONLINE     NORMAL  AFD:TEST09
I will add Disk TEST08 to TEST_DG diskgroup . Login to ASM as sysasm and execute below command
SQL> alter diskgroup TEST_DG add disk 'AFD:TEST08';
Diskgroup altered.
So the Diskgroup has been added successfully but as you can see the disk has been assigned a default failgroup because I have not specified any failgroup name, which is of course incorrect  and I must drop this disk and add it correctly.
Note1:-Each disk is assigned to its own failure group if no failure group name specified while adding the disk or creating a diskgroup
Note2:-Adding/Dropping the Disk from a disk group triggers rebalance operation which is a performance overhead. You can check the rebalance operation status from  V$ASM_OPERATION 
Note3:- You can add a Disk in the Diskgroup with force option even if this disk was previously a member of a disk group that no longer exists or no longer mounted and therefore be very careful while using force because you will not be able to mount the diskgroup again if the disk was belonging a DG which was dismounted

How to Drop a Disk from ASM Disk Group

SQL> alter diskgroup test_dg drop disk TEST08;
Diskgroup altered.

How to Replace Disks in ASM Disk Group

A disk or multiple disks in a disk group can be replaced, rather than dropped and added back
Compatible.asm should be 12.1.0.0.0 or higher.
I lost the disk TEST06 which I replaced with good available disk TEST08 instead of dropping and adding the disk
SQL>  alter diskgroup TEST_DG replace disk TEST06 with 'AFD:TEST08';
Diskgroup altered.

How to Rename a Disk in a Disk Group

To rename the disk in the diskgroup the DG must be mounted in restricted mode else you will encounter following error
SQL> alter diskgroup TEST_DG rename disk 'TEST06' to 'TEST08';
alter diskgroup TEST_DG rename disk 'TEST06' to 'TEST08'
*
ERROR at line 1:

ORA-31020: The operation is not allowed, Reason: disk group is NOT mounted in RESTRICTED state.

SQL> alter diskgroup TEST_DG dismount;
Diskgroup altered.
SQL> alter diskgroup TEST_DG mount restricted;
Diskgroup altered.
SQL> alter diskgroup TEST_DG rename disk 'TEST06' to 'TEST08';
Diskgroup altered.
Note4:- Diskgroups mounted in restricted mode are not available to the Database and therefore operation involves downtime

How to Resize Disk in Disk Group

Note5:-When resizing disks in a disk group, all the disks must be of equal size
SQL> alter diskgroup TEST_DG resize all size 1G;
Diskgroup altered.

How to Change Diskgroup Attributes

SQL> select NAME,VALUE from v$asm_attribute where GROUP_NUMBER='4' and NAME like '%compa%';
NAME                                               VALUE
-------------------------------------------------- ------------------------------
compatible.asm                                     11.2.0.2.0
compatible.rdbms                                   10.1.0.0.0
compatible.advm                                    11.2.0.2.0
SQL>  alter diskgroup TEST_DG set attribute 'compatible.asm'='12.2.0.0';
Diskgroup altered.
SQL> select NAME,VALUE from v$asm_attribute where GROUP_NUMBER='4' and NAME like '%compa%';
NAME                                               VALUE
-------------------------------------------------- ------------------------------
compatible.asm                                     12.2.0.0.0
compatible.rdbms                                   10.1.0.0.0
compatible.advm                                    11.2.0.2.0

How to Undrop Disks in Diskgroup

The UNDROP DISKS clause of the ALTER DISKGROUP statement enables you to cancel all pending drops of disks within disk groups.
If a drop disk operation has completed, then this statement cannot be used to restore it. This statement cannot be used to restore disks that are being dropped as the result of a DROP DISKGROUP statement, or for disks that are being dropped using the FORCE clause.

SQL> select dg.NAME,ds.NAME,ds.MOUNT_STATUS,ds.HEADER_STATUS,ds.MODE_STATUS,ds.STATE,ds.FAILGROUP,ds.LABEL,ds.PATH from v$asm_diskgroup dg,v$asm_disk ds
where dg.GROUP_NUMBER=ds.GROUP_NUMBER and dg.NAME='TEST_DG'; 
NAME            NAME            MOUNT_S HEADER_STATU MODE_ST STATE    FAILGROUP  LABEL      PATH
--------------- --------------- ------- ------------ ------- -------- ---------- ---------- ----------
TEST_DG         TEST06          CACHED  MEMBER       ONLINE  NORMAL   TEST06     TEST06     AFD:TEST06
TEST_DG         TEST07          CACHED  MEMBER       ONLINE  NORMAL   TEST07     TEST07     AFD:TEST07
TEST_DG         TEST08          CACHED  MEMBER       ONLINE  NORMAL   TEST08     TEST08     AFD:TEST08
TEST_DG         TEST09          CACHED  MEMBER       ONLINE  NORMAL   TEST09     TEST09     AFD:TEST09
I have 4 Disks in my Diskgroup TEST_DG and I wanted to test the undrop functionality by dropping and undropping disk TEST07
SQL> ALTER DISKGROUP TEST_DG DROP DISK 'TEST07';
Diskgroup altered.
SQL> select dg.NAME,ds.NAME,ds.MOUNT_STATUS,ds.HEADER_STATUS,ds.MODE_STATUS,ds.STATE,ds.FAILGROUP,ds.LABEL,ds.PATH from v$asm_diskgroup dg,v$asm_disk ds
where dg.GROUP_NUMBER=ds.GROUP_NUMBER and dg.NAME='TEST_DG'; 
NAME            NAME            MOUNT_S HEADER_STATU MODE_ST STATE    FAILGROUP  LABEL      PATH
--------------- --------------- ------- ------------ ------- -------- ---------- ---------- ----------
TEST_DG         TEST06          CACHED  MEMBER       ONLINE  NORMAL   TEST06     TEST06     AFD:TEST06
TEST_DG         TEST07          CACHED  MEMBER       ONLINE  DROPPING TEST07     TEST07     AFD:TEST07
TEST_DG         TEST08          CACHED  MEMBER       ONLINE  NORMAL   TEST08     TEST08     AFD:TEST08
TEST_DG         TEST09          CACHED  MEMBER       ONLINE  NORMAL   TEST09     TEST09     AFD:TEST09
At this point as you can see the disk is in dropping status and not yet dropped. The data stored in the disk is being relocated to other available disks and we can check the details about the same by querying v$asm_operation view.
As long as the disk is not dropped we can undrop it
SQL> select * from v$asm_operation;
GROUP_NUMBER OPERA PASS      STAT      POWER     ACTUAL      SOFAR   EST_WORK   EST_RATE EST_MINUTES ERROR_CODE                                       CON_ID
------------ ----- --------- ---- ---------- ---------- ---------- ---------- ---------- ----------- -------------------------------------------- ----------
           4 REBAL COMPACT   WAIT          1          1          0          0          0           0                                                       0
           4 REBAL REBALANCE RUN           1          1         72       3059       1388           2                                                       0
           4 REBAL REBUILD   DONE          1          1          0          0          0           0                                                       0
           4 REBAL RESYNC    DONE          1          1          0          0          0           0                                                       0
SQL> ALTER DISKGROUP TEST_DG UNDROP DISKS;
Diskgroup altered.
SQL> select dg.NAME,ds.NAME,ds.MOUNT_STATUS,ds.HEADER_STATUS,ds.MODE_STATUS,ds.STATE,ds.FAILGROUP,ds.LABEL,ds.PATH from v$asm_diskgroup dg,v$asm_disk ds
where dg.GROUP_NUMBER=ds.GROUP_NUMBER and dg.NAME='TEST_DG'; 
NAME            NAME            MOUNT_S HEADER_STATU MODE_ST STATE    FAILGROUP  LABEL      PATH
--------------- --------------- ------- ------------ ------- -------- ---------- ---------- ----------
TEST_DG         TEST06          CACHED  MEMBER       ONLINE  NORMAL   TEST06     TEST06     AFD:TEST06
TEST_DG         TEST07          CACHED  MEMBER       ONLINE  NORMAL   TEST07     TEST07     AFD:TEST07
TEST_DG         TEST08          CACHED  MEMBER       ONLINE  NORMAL   TEST08     TEST08     AFD:TEST08
TEST_DG         TEST09          CACHED  MEMBER       ONLINE  NORMAL   TEST09     TEST09     AFD:TEST09
And as you can see the disk status is again normal and not dropping any more. 
SQL> select * from v$asm_operation;
GROUP_NUMBER OPERA PASS      STAT      POWER     ACTUAL      SOFAR   EST_WORK   EST_RATE EST_MINUTES ERROR_CODE                                       CON_ID
------------ ----- --------- ---- ---------- ---------- ---------- ---------- ---------- ----------- -------------------------------------------- ----------
           4 REBAL COMPACT   WAIT          1          1          0          0          0           0                                                       0
           4 REBAL REBALANCE RUN           1          1        242       2298        927           2                                                       0
           4 REBAL REBUILD   DONE          1          1          0          0          0           0                                                       0
           4 REBAL RESYNC    DONE          1          1          0          0          0           0                                                       0

How to Create ADVM (ASM Dynamic Volume Manager) Volume in Diskgroup

SQL> alter diskgroup TEST_DG add volume vol1 size 2G;
Diskgroup altered.
Once you have created the Volume you can mount it on OS level and you can use it as regular mount point
$mkfs -t acfs  /dev/asm/vol1-467
As root user
#mount -t acfs  /dev/asm/vol1-467 /acfs_test

Comments

Post a Comment

Popular posts from this blog

How to Power On/off Oracle Exadata Machine

<<Back to Exadata Main Page How to Power On/off Oracle Exadata Machine Oracle Exadata machines can be powered on/off either by pressing the power button on front of the server or by logging in to the ILOM interface. Powering on servers using  button on front of the server The power on sequence is as follows. 1. Start Rack, including switches  Note:- Ensure the switches have had power applied for a few minutes to complete power on  configuration before starting Exadata Storage Servers 2.Start Exadata Storage Servers  Note:- Ensure all Exadata Storage Servers complete the boot process before starting the   database servers 3. Start Database Servers Powering On Servers Remotely using ILOM The ILOM can be accessed using the Web console, the command-line interface (CLI), IPMI, or SNMP. For example, to apply power to server dm01cel01 using IPMI, where dm01cel01-ilom is the host name of the ILOM for the server to be powered on, run the
Post a Comment
Read more

ORA-28374: typed master key not found in wallet

<<Back to Oracle DB Security Main Page ORA-46665: master keys not activated for all PDBs during REKEY SQL> ADMINISTER KEY MANAGEMENT SET KEY FORCE KEYSTORE IDENTIFIED BY xxxx WITH BACKUP CONTAINER = ALL ; ADMINISTER KEY MANAGEMENT SET KEY FORCE KEYSTORE IDENTIFIED BY xxxx WITH BACKUP CONTAINER = ALL * ERROR at line 1: ORA-46665: master keys not activated for all PDBs during REKEY I found following in the trace file REKEY: Create Key in PDB 3 resulted in error 46658 *** 2019-02-06T15:27:04.667485+01:00 (CDB$ROOT(1)) REKEY: Activation of Key AdnU5OzNP08Qv1mIyXhP/64AAAAAAAAAAAAAAAAAAAAAAAAAAAAA in PDB 3 resulted in error 28374 REKEY: Keystore needs to be restored from the REKEY backup.Aborting REKEY! Cause: All this hassle started because I accidently deleted the wallet and all wallet backup files too and also forgot the keystore password. There was no way to restore the wallet back. Fortunately in my case the PDB which had encrypted data was supposed to be deco
7 comments
Read more

How to Find VIP of an Oracle RAC Cluster

<<Back to Oracle RAC Main Page How to Find Out VIP of an Oracle RAC Cluster Login clusterware owner (oracle) and execute the below command to find out the VIP hostname used in Oracle RAC $ olsnodes -i node1     node1-vip node2     node2-vip OR $ srvctl config nodeapps -viponly Network 1 exists Subnet IPv4: 10.0.0.0/255.255.0.0/bondeth0, static Subnet IPv6: Ping Targets: Network is enabled Network is individually enabled on nodes: Network is individually disabled on nodes: VIP exists: network number 1, hosting node node1 VIP Name: node1-vip VIP IPv4 Address: 10.0.0.1 VIP IPv6 Address: VIP is enabled. VIP is individually enabled on nodes: VIP is individually disabled on nodes: VIP exists: network number 1, hosting node node2 VIP Name: node2-vip VIP IPv4 Address: 10.0.0.2 VIP IPv6 Address: VIP is enabled. VIP is individually enabled on nodes: VIP is individually disabled on nodes:
1 comment
Read more

ORA-16905: The member was not enabled yet

<<Back to Oracle DataGuard Main Page ORA-16905 Physical Standby Database is disabled DGMGRL> show configuration; Configuration - DG_ORCL1P   Protection Mode: MaxPerformance   Members:   ORCL1PP - Primary database     ORCL1PS - Physical standby database (disabled)       ORA-16905: The member was not enabled yet. Fast-Start Failover:  Disabled Configuration Status: SUCCESS   (status updated 58 seconds ago) DGMGRL> DGMGRL> enable database 'ORCL1PS'; Enabled. DGMGRL>  show configuration; Configuration - DG_ORCL1P   Protection Mode: MaxPerformance   Members:   ORCL1PP - Primary database     ORCL1PS - Physical standby database Fast-Start Failover:  Disabled Configuration Status: SUCCESS   (status updated 38 seconds ago)
Post a Comment
Read more

How to Switch Log File from All Instances in RAC

<<Back to Oracle RAC Main Page Switch The Log File of All Instances in Oracle RAC. In many cases you need to switch the logfile of the database. You can switch logfile using alter system switch logfile command but if you want to switch the logfile from all the instances you need to execute the command on all the instances individually and therefore you must login on all the instances. You can avoid this and switch logfile of all instances by just running the below command from any of the instance in RAC database SQL> ALTER SYSTEM SWITCH ALL LOGFILE;   System altered.
Post a Comment
Read more

ORA-65104: operation not allowed on an inactive pluggable database alter pluggable database open

<<Back to DB Administration Main Page ORA-65104: operation not allowed on an inactive pluggable database SQL> alter pluggable database TEST_CLON open; alter pluggable database TEST_CLON open * ERROR at line 1: ORA-65104: operation not allowed on an inactive pluggable database Cause The pluggable database status was UNUSABLE. It was still being created or there was an error during the create operation. A PDB can only be opened if it is successfully created and its status is marked as NEW in cdb_pdbs.status column SQL> select PDB_NAME,STATUS from cdb_pdbs; PDB_NAME             STATUS -------------------- --------------------------- PDB$SEED             NORMAL TEST_CLON            UNUSABLE Solution:  Drop the PDB and create it again. Related Posts How to Clone Oracle PDB (Pluggable Database) with in the Same Container
Post a Comment
Read more

ORA-46630: keystore cannot be created at the specified location

<<Back to DB Administration Main Page ORA-46630: keystore cannot be created at the specified location CDB011> ADMINISTER KEY MANAGEMENT CREATE KEYSTORE '+DATAC4/CDB01/wallet/' IDENTIFIED BY "xxxxxxx"; ADMINISTER KEY MANAGEMENT CREATE KEYSTORE '+DATAC4/CDB01/wallet/' IDENTIFIED BY "EncTest123" * ERROR at line 1: ORA-46630: keystore cannot be created at the specified location Cause  Creating a keystore at a location where there is already a keystore exists Solution To solve the problem, use a different location to create a keystore (use ENCRYPTION_WALLET_LOCATION in sqlnet.ora file to specify the keystore location), or move this ewallet.p12 file to some other location. Note: Oracle does not recommend deleting keystore file (ewallet.p12) that belongs to a database. If you have multiple keystores, you can choose to merge them rather than deleting either of them.
Post a Comment
Read more

Starting RMAN and connecting to Database

  <<Back to Oracle Backup & Recovery Main Page Starting RMAN and connecting to Database Starting RMAN and connecting to Database To start RMAN you need to set the environment and type rman and press enter. You can connect to database either using connect command or using command line option. using command line option localhost:$ export ORACLE_HOME=/ora_app/product/18c/dbd2 localhost:$ export PATH=$ORACLE_HOME/bin:$PATH localhost:$ export ORACLE_SID=ORCL1P localhost:$ rman target / Recovery Manager: Release 18.0.0.0.0 - Production on Sun Apr 4 08:11:01 2021 Version 18.11.0.0.0 Copyright (c) 1982, 2018, Oracle and/or its affiliates.  All rights reserved. connected to target database: ORCL1P (DBID=4215484517) RMAN> using connect option localhost:$ rman RMAN> connect target sys@ORCL1P  target database Password:******** connected to target database: ORCL1P (DBID=4215484517) NOTE: To use connect command you need to ensure that  you have proper TNS sentry for database (ORCL
Post a Comment
Read more

How to Attach to a Datapump Job and Check Status of Export or Import

<<Back to Oracle DATAPUMP Main Page How to check the progress of  export or import Jobs You can attach to the export/import  job using ATTACH parameter of oracle datapump utility. Once you are attached to the job you check its status by typing STATUS command. Let us see how Step1>  Find the Export/Import Job Name You can find the datapump job information from  DBA_DATAPUMP_JOBS or  USER_DATAPUMP_JOBS view. SQL> SELECT OWNER_NAME,JOB_NAME,OPERATION,JOB_MODE,STATE from DBA_DATAPUMP_JOBS; OWNER_NAME JOB_NAME                       OPERATION            JOB_MODE   STATE ---------- ------------------------------ -------------------- ---------- ---------- SYSTEM     SYS_EXPORT_FULL_02             EXPORT               FULL       EXECUTING OR You can also find the job name for export/import in logfile in beginning itself. Step2>Attach to the Job and check status One you get the Export/Import Job Name attach the job and check its status. You can attach or det
7 comments
Read more

Step by Step how to Create Virtual Machine using Virtualbox

<<Back to Linux Main Page How to Create New Virtual Machine Using Oracle Virtual Box Step1:   Open Oracle Virtual Box --> Click New Provide Name, Type and Version as shown in the image below and click Next  Step2:  Adjust memory (RAM) as per the requirement and availability   and click Next.  NOTE:- Remember to leave enough memory for the host OS to work properly.  Step3:   Select the option to create a new virtual hard drive and click "Create"  (erzeugen) button.  Step4:  Accept Default and click next (weiter)   Step5: Accept the dynamically allocated option by clicking the "Next" (weiter) button.  Step6:  If you don't want to use the defaults, enter the required location, name and size of the virtual disk and click the "Create" (erzeugen) button. Note:- At this point your virtual machine is created and ready for OS installation Preparing the Virtual machine for Oracle RAC Installation Step1:   Select t
Post a Comment
Read more