3 Configuring Oracle Clusterware and Oracle Database Storage

3.1.1 Overview of Storage Options

Use the following overview to help you select your storage option:

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3.1.2 Checking for Available Shared Storage with CVU

To check for all shared file systems available across all nodes on the cluster with an NFS file system, use the following command:

/mountpoint/clusterware/cluvfy/runcluvfy.sh comp ssa -n node_list

If you want to check the shared accessibility of a specific shared storage type to specific nodes in your cluster, then use the following command syntax:

/mountpoint/clusterware/cluvfy/runcluvfy.sh comp ssa -n node_list -s storageID_list

In the preceding syntax examples, the variable mountpoint is the mountpoint path of the installation media, the variable node_list is the list of nodes you want to check, separated by commas, and the variable storageID_list is the list of storage device IDs for the storage devices managed by the file system type that you want to check.

For example, if you want to check the shared accessibility from node1 and node2 of storage devices /dev/sdb and /dev/sdc, and your mountpoint is /dev/dvdrom/, then enter the following command:

/dev/dvdrom/clusterware/cluvfy/runcluvfy.sh comp ssa -n node1,node2 -s /dev/sdb,/dev/sdc

If you do not specify specific storage device IDs in the command, then the command searches for all available storage devices connected to the nodes on the list

3.2.1 Requirements for Using a File System for Oracle Clusterware Files

To use a file system for Oracle Clusterware files, the file system must comply with the following requirements:

• To use an NFS file system, it must be on a certified NAS device.

  
  

  Note: If you are using a shared file system on a NAS device to store a shared Oracle home directory for Oracle Clusterware or RAC, then you must use the same NAS device for Oracle Clusterware file storage.

  
  

• If you choose to place your Oracle Cluster Registry (OCR) files on a shared file system, then one of the following must be true:

  • The disks used for the file system are on a highly available storage device.

  • At least two file systems are mounted, and use the features of Oracle Database 10g Release 2 (10.2) to provide redundancy for the OCR.

• If you intend to use a shared file system to store database files, then use at least two independent file systems, with the database files on one file system, and the recovery files on a different file system.

• The oracle user must have write permissions to create the files in the path that you specify.

Use Table 3-1 to determine the partition size for shared file systems.

In Table 3-1, the total required volume size is cumulative. For example, to store all files on the shared file system, you should have at least 3.4 GB of storage available over a minimum of two volumes.

3.2.2 Checking NFS Buffer Size Parameters

If you are using NFS, then you must set the values for the NFS buffer size parameters rsize and wsize to at least 16384. Oracle recommends that you use the value 32768.

For example, if you decide to use rsize and wsize buffer settings with the value 32768, and your NFS server is named nfs_server, then update the /etc/fstab file on each node with an entry similar to the following:

nfs_server:/vol/DATA/oradata  /home/oracle/netapp     nfs\   rw,hard,nointr,rsize=32768,wsize=32768,tcp,noac,vers=3  1 2

3.2.3 Creating Required Directories for Oracle Clusterware Files on Shared File Systems

Use the following instructions to create directories for Oracle Clusterware files. If you intend to use a file system to store Oracle Clusterware files, then you can also configure file systems for the Oracle Database and recovery files.

To create directories for the Oracle Clusterware files on separate file systems from the Oracle base directory, follow these steps:

1. If necessary, configure the shared file systems that you want to use and mount them on each node.

   
   

   Note: The mount point that you use for the file system must be identical on each node. Ensure that the file systems are configured to mount automatically when a node restarts.

   
   

2. Use the bdf command to determine the free disk space on each mounted file system.

3. From the display, identify the file systems that you want to use:

   File Type	File System Requirements
   Oracle Clusterware files	Choose a file system with at least 120 MB of free disk space
   Database files	Choose either: A single file system with at least 1.2 GB of free disk space Two or more file systems with at least 1.2 GB of free disk space in total
   Recovery files	Choose a file system with at least 2 GB of free disk space.

   
   

   If you are using the same file system for more than one type of file, then add the disk space requirements for each type to determine the total disk space requirement.

4. Note the names of the mount point directories for the file systems that you identified.

5. If the user performing installation (typically, oracle) has permissions to create directories on the disks where you plan to install Oracle Clusterware and Oracle Database, then OUI creates the Oracle Clusterware file directory, and DBCA creates the Oracle Database file directory, and the Recovery file directory.

   If the user performing the installation does not have write access, then you must create these directories manually using commands similar to the following to create the recommended subdirectories in each of the mount point directories and set the appropriate owner, group, and permissions on them:

   • Oracle Clusterware file directory:

     # mkdir /mount_point/oracrs
     # chown oracle:oinstall /mount_point/oracrs
     # chmod 775 /mount_point/oracrs
     
     

   • Database file directory:

     # mkdir /mount_point/oradata
     # chown oracle:oinstall /mount_point/oradata
     # chmod 775 /mount_point/oradata
     
     

   • Recovery file directory (flash recovery area):

     # mkdir /mount_point/flash_recovery_area
     # chown oracle:oinstall /mount_point/flash_recovery_area
     # chmod 775 /mount_point/flash_recovery_area
     
     

By making the Oracle user the owner of these directories, this permits them to be read by multiple Oracle homes, including those with different OSDBA groups.

When you have completed creating subdirectories in each of the mount point directories, and set the appropriate owner, group, and permissions, you have completed NFS configuration.

3.3.1 Identifying Required Raw Partitions for Clusterware Files

Table 3-2 lists the number and size of the raw partitions that you must configure for Oracle Clusterware files.

3.3.2 Disabling Operating System Activation of Shared Volume Groups

To prevent the operating system from activating shared volume groups when it starts, you must edit the /etc/lvmrc file on every node, as follows:

1. Create a backup copy of the /etc/lvmrc file:

   # cp /etc/lvmrc /etc/lvmrc_orig
   
   

2. Open the /etc/lvmrc file in any text editor and search for the AUTO_VG_ACTIVATE flag.

3. If necessary, change the value of the AUTO_VG_ACTIVATE flag to 0, to disable automatic volume group activation, as follows:

   AUTO_VG_ACTIVATE=0
   
   

4. Search for the custom_vg_activation function in the /etc/lvmrc file.

5. Add vgchange commands to the function, as shown in the following example, to automatically activate existing local volume groups:

   custom_vg_activation()
   {
           # e.g. /sbin/vgchange -a y -s
           #      parallel_vg_sync "/dev/vg00 /dev/vg01"
           #      parallel_vg_sync "/dev/vg02 /dev/vg03"
   
           /sbin/vgchange -a y vg00
           /sbin/vgchange -a y vg01
           /sbin/vgchange -a y vg02
   
           return 0
   }
   
   

   In this example, vg00, vg01, and vg02 are the volume groups that you want to activate automatically when the system restarts.

3.3.3 Configuring Raw Disk Devices Without HP ServiceGuard Extension

If you are installing Oracle Clusterware or Oracle Clusterware and Oracle Real Application Clusters on an HP-UX cluster without HP ServiceGuard Extension for RAC, then you must use shared raw disk devices for the Oracle Clusterware files. You can also use shared raw disk devices for database file storage, however, Oracle recommends that you use Automatic Storage Management to store database files in this situation. This section describes how to configure the shared raw disk devices for Oracle Clusterware files (Oracle Cluster Registry and Oracle Clusterware voting disk) and database files.

Table 3-3 lists the number and size of the raw disk devices that you must configure for database files.

dbname_system_raw_500m

dbname_sysaux_raw_800m

dbname_undotbsn_raw_500m

dbname_temp_raw_250m

dbname_example_raw_160m

dbname_users_raw_120m

dbname_redon_m_raw_120m

dbname_control{1|2}_raw_110m

dbname_spfile_raw_5m

dbname_pwdfile_raw_5m

To configure shared raw disk devices for Oracle Clusterware files, database files, or both:

1. If you intend to use raw disk devices for database file storage, then choose a name for the database that you want to create.

   The name that you choose must start with a letter and have no more than four characters, for example, orcl.

2. Identify or configure the required disk devices.

   The disk devices must be shared on all of the cluster nodes.

3. To ensure that the disks are available, enter the following command on every node:

   # /usr/sbin/ioscan -fun -C disk
   
   

   The output from this command is similar to the following:

   Class  I  H/W Path    Driver S/W State   H/W Type     Description
   ==========================================================================
   disk    0  0/0/1/0.6.0 sdisk  CLAIMED     DEVICE       HP   DVD-ROM 6x/32x
                          /dev/dsk/c0t6d0   /dev/rdsk/c0t6d0
   disk    1  0/0/1/1.2.0 sdisk  CLAIMED     DEVICE      SEAGATE ST39103LC
                          /dev/dsk/c1t2d0   /dev/rdsk/c1t2d0
   
   

   This command displays information about each disk attached to the system, including the block device name (/dev/dsk/cxtydz) and the character raw device name (/dev/rdsk/cxtydz).

4. If the ioscan command does not display device name information for a device that you want to use, then enter the following command to install the special device files for any new devices:

   # /usr/sbin/insf -e
   
   

5. For each disk that you want to use, enter the following command on any node to verify that it is not already part of an LVM volume group:

   # /sbin/pvdisplay /dev/dsk/cxtydz
   
   

   If this command displays volume group information, then the disk is already part of a volume group. The disks that you choose must not be part of an LVM volume group.

   
   

   Note: If you are using different volume management software, for example VERITAS Volume Manager, then refer to the appropriate documentation for information about verifying that a disk is not in use.

   
   

6. If the ioscan command shows different device names for the same device on any node, then:

   1. Change directory to the /dev/rdsk directory.

   2. Enter the following command to list the raw disk device names and their associated major and minor numbers:

      # ls -la
      
      

      The output from this command is similar to the following for each disk device:

      crw-r--r--   1 bin        sys        188 0x032000 Nov  4  2003 c3t2d0
      
      

      In this example, 188 is the device major number and 0x32000 is the device minor number.

   3. Enter the following command to create a new device file for the disk that you want to use, specifying the same major and minor number as the existing device file:

      
      

      Note: Oracle recommends that you use the alternative device file names shown in the previous table.

      
      

      # mknod ora_ocr_raw_100m c 188 0x032000
      
      

   4. Repeat these steps on each node, specifying the correct major and minor numbers for the new device files on each node.

7. Enter commands similar to the following on every node to change the owner, group, and permissions on the character raw device file for each disk device that you want to use:

   
   

   Note: If you are using a multi-pathing disk driver with Automatic Storage Management, then ensure that you set the permissions only on the correct logical device name for the disk. If you created an alternative device file for the device, then set the permissions on that device file.

   
   

   • OCR:

     # chown root:oinstall /dev/rdsk/cxtydz
     # chmod 640 /dev/rdsk/cxtydz
     
     

   • Oracle Clusterware voting disk or database files:

     # chown oracle:dba /dev/rdsk/cxtydz
     # chmod 660 /dev/rdsk/cxtydz
     
     

8. If you are using raw disk devices for database files, then follow these steps to create the Oracle Database Configuration Assistant raw device mapping file:

   
   

   Note: You must complete this procedure only if you are using raw devices for database files. The Oracle Database Configuration Assistant raw device mapping file enables Oracle Database Configuration Assistant to identify the appropriate raw disk device for each database file. You do not specify the raw devices for the Oracle Clusterware files in the Oracle Database Configuration Assistant raw device mapping file.

   
   

   1. Set the ORACLE_BASE environment variable to specify the Oracle base directory that you identified or created previously:

      • Bourne, Bash, or Korn shell:

        $ ORACLE_BASE=/u01/app/oracle ; export ORACLE_BASE
        
        

      • C shell:

        % setenv ORACLE_BASE /u01/app/oracle
        
        

   2. Create a database file subdirectory under the Oracle base directory and set the appropriate owner, group, and permissions on it:

      # mkdir -p $ORACLE_BASE/oradata/dbname
      # chown -R oracle:oinstall $ORACLE_BASE/oradata
      # chmod -R 775 $ORACLE_BASE/oradata
      
      

      In this example, dbname is the name of the database that you chose previously.

   3. Change directory to the $ORACLE_BASE/oradata/dbname directory.

   4. Using any text editor, create a text file similar to the following that identifies the disk device file name associated with each database file.

      Oracle recommends that you use a file name similar to dbname_raw.conf for this file.

      
      

      Note: The following example shows a sample mapping file for a two-instance RAC cluster. Some of the devices use alternative disk device file names. Ensure that the device file name that you specify identifies the same disk device on all nodes.

      
      

      system=/dev/rdsk/c2t1d1
      sysaux=/dev/rdsk/c2t1d2
      example=/dev/rdsk/c2t1d3
      users=/dev/rdsk/c2t1d4
      temp=/dev/rdsk/c2t1d5
      undotbs1=/dev/rdsk/c2t1d6
      undotbs2=/dev/rdsk/c2t1d7
      redo1_1=/dev/rdsk/c2t1d8
      redo1_2=/dev/rdsk/c2t1d9
      redo2_1=/dev/rdsk/c2t1d10
      redo2_2=/dev/rdsk/c2t1d11
      control1=/dev/rdsk/c2t1d12
      control2=/dev/rdsk/c2t1d13
      spfile=/dev/rdsk/dbname_spfile_raw_5m
      pwdfile=/dev/rdsk/dbname_pwdfile_raw_5m
      
      

      In this example, dbname is the name of the database.

      Use the following guidelines when creating or editing this file:

      • Each line in the file must have the following format:

        database_object_identifier=device_file_name
        
        

        The alternative device file names suggested in the previous table include the database object identifier that you must use in this mapping file. For example, in the following alternative disk device file name, redo1_1 is the database object identifier:

        rac_redo1_1_raw_120m
        
        

      • For a RAC database, the file must specify one automatic undo tablespace datafile (undotbsn) and two redo log files (redon_1, redon_2) for each instance.

      • Specify at least two control files (control1, control2).

      • To use manual instead of automatic undo management, specify a single RBS tablespace datafile (rbs) instead of the automatic undo management tablespace data files.

   5. Save the file and note the file name that you specified.

   6. When you are configuring the oracle user's environment later in this chapter, set the DBCA_RAW_CONFIG environment variable to specify the full path to this file.

9. When you are installing Oracle Clusterware, you must enter the paths to the appropriate device files when prompted for the path of the OCR and Oracle Clusterware voting disk, for example:

   /dev/rdsk/cxtydz
   
   

3.3.4 Configuring Shared Raw Logical Volumes With HP ServiceGuard Extension

This section describes how to configure shared raw logical volumes for Oracle Clusterware and database file storage for an Oracle Real Application Clusters (RAC) database. The procedures in this section describe how to create a new shared volume group that contains the logical volumes required for both types of files.

To use shared raw logical volumes, HP ServiceGuard Extension for RAC must be installed on all cluster nodes. If HP ServiceGuard Extension for RAC is not installed, then you can use shared raw disk devices to store the Oracle Clusterware or database files. However, Oracle recommends that you use this method only for the Oracle Clusterware files and use an alternative method such as Automatic Storage Management for database file storage.

Before you continue, review the following guidelines which contain important information about using shared logical volumes with this release of RAC:

• You must use shared volume groups for Oracle Clusterware and database files.

• The Oracle Clusterware files require less than 200 MB of disk space. To make efficient use of the disk space in a volume group, Oracle recommends that you use the same shared volume group for the logical volumes for both the Oracle Clusterware files and the database files.

• If you are upgrading an existing Oracle9i release 2 RAC installation that uses raw logical volumes, then you can use the existing SRVM configuration repository logical volume for the OCR and create a new logical volume in the same volume group for the Oracle Clusterware voting disk. However, before you install Oracle Clusterware, you must remove this volume group from any ServiceGuard package that currently activates it.

  
  

  See Also: The HP ServiceGuard or HP ServiceGuard Extension for RAC documentation for information about removing a volume group from a ServiceGuard package.

  
  
  
  

  Note: If you are upgrading a database, then you must also create a new logical volume for the SYSAUX tablespace. Refer to the "Create Raw Logical Volumes in the New Volume Group" section for more information about the requirements for the Oracle Clusterware voting disk and SYSAUX logical volumes.

  
  

• You must use either your own startup script or a ServiceGuard package to activate new or existing volume groups that contain only database files (not Oracle Clusterware files).

  
  

  See Also: The HP ServiceGuard documentation for information about creating a ServiceGuard package to activate a shared volume group for RAC.

  
  

• All shared volume groups that you intend to use for Oracle Clusterware or database files must be activated in shared mode before you start the installation.

• All shared volume groups that you are using for RAC, including the volume group that contains the Oracle Clusterware files, must be specified in the cluster configuration file using the parameter OPS_VOLUME_GROUP.

  
  

  Note: If you create a new shared volume group for RAC on an existing HP ServiceGuard cluster, then you must reconfigure and restart the cluster before installing Oracle Clusterware. Refer to the HP ServiceGuard documentation for information about configuring the cluster and specifying shared volume groups.

  
  

• The procedures in this section describe how to create basic volumes groups and volumes. If you want to configure more complex volumes, using mirroring for example, then use this section in conjunction with the HP ServiceGuard documentation.

# /sbin/vgchange -a s vg_name

3.3.5 Create the Oracle Database Configuration Assistant Raw Device Mapping File

To enable Oracle Database Configuration Assistant to identify the appropriate raw device for each database file, you must create a raw device mapping file, as follows:

1. Set the ORACLE_BASE environment variable to specify the Oracle base directory that you identified or created previously:

   • Bourne, Bash, or Korn shell:

     $ ORACLE_BASE=/u01/app/oracle ; export ORACLE_BASE
     
     

   • C shell:

     % setenv ORACLE_BASE /u01/app/oracle
     
     

2. Create a database file subdirectory under the Oracle base directory and set the appropriate owner, group, and permissions on it:

   # mkdir -p $ORACLE_BASE/oradata/dbname
   # chown -R oracle:oinstall $ORACLE_BASE/oradata
   # chmod -R 775 $ORACLE_BASE/oradata
   
   

   In this example, dbname is the name of the database that you chose previously.

3. Change directory to the $ORACLE_BASE/oradata/dbname directory.

4. Enter a command similar to the following to create a text file that you can use to create the raw device mapping file:

   # find /dev/vg_name -user oracle -name 'r*' -print > dbname_raw.conf
   
   

5. Edit the dbname_raw.conf file in any text editor to create a file similar to the following:

   
   

   Note: The following example shows a sample mapping file for a two-instance RAC cluster.

   
   

   system=/dev/vg_name/rdbname_system_raw_500m
   sysaux=/dev/vg_name/rdbname_sysaux_raw_800m
   example=/dev/vg_name/rdbname_example_raw_160m
   users=/dev/vg_name/rdbname_users_raw_120m
   temp=/dev/vg_name/rdbname_temp_raw_250m
   undotbs1=/dev/vg_name/rdbname_undotbs1_raw_500m
   undotbs2=/dev/vg_name/rdbname_undotbs2_raw_500m
   redo1_1=/dev/vg_name/rdbname_redo1_1_raw_120m
   redo1_2=/dev/vg_name/rdbname_redo1_2_raw_120m
   redo2_1=/dev/vg_name/rdbname_redo2_1_raw_120m
   redo2_2=/dev/vg_name/rdbname_redo2_2_raw_120m
   control1=/dev/vg_name/rdbname_control1_raw_110m
   control2=/dev/vg_name/rdbname_control2_raw_110m
   spfile=/dev/vg_name/rdbname_spfile_raw_5m
   pwdfile=/dev/vg_name/rdbname_pwdfile_raw_5m
   
   

   In this example:

   • vg_name is the name of the volume group

   • dbname is the name of the database

   Use the following guidelines when creating or editing this file:

   • Each line in the file must have the following format:

     database_object_identifier=logical_volume
     
     

     The logical volume names suggested in this manual include the database object identifier that you must use in this mapping file. For example, in the following logical volume name, redo1_1 is the database object identifier:

     /dev/oracle_vg/rrac_redo1_1_raw_120m
     
     

   • The file must specify one automatic undo tablespace datafile (undotbsn) and two redo log files (redon_1, redon_2) for each instance.

   • Specify at least two control files (control1, control2).

   • To use manual instead of automatic undo management, specify a single RBS tablespace datafile (rbs) instead of the automatic undo management tablespace data files.

   • Save the file and note the file name that you specified.

   • When you are configuring the oracle user's environment later in this chapter, set the DBCA_RAW_CONFIG environment variable to specify the full path to this file.

3.5.1 Identifying Storage Requirements for Automatic Storage Management

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To identify the storage requirements for using Automatic Storage Management, you must determine how many devices and the amount of free disk space that you require. To complete this task, follow these steps:

1. Determine whether you want to use Automatic Storage Management for Oracle Database files, recovery files, or both.

   
   

   Note: You do not have to use the same storage mechanism for database files and recovery files. You can use the file system for one file type and Automatic Storage Management for the other. If you choose to enable automated backups and you do not have a shared file system available, then you must choose Automatic Storage Management for recovery file storage.

   
   

   If you enable automated backups during the installation, you can choose Automatic Storage Management as the storage mechanism for recovery files by specifying an Automatic Storage Management disk group for the flash recovery area. Depending on how you choose to create a database during the installation, you have the following options:

   • If you select an installation method that runs Database Configuration Assistant in interactive mode (for example, by choosing the Advanced database configuration option) then you can decide whether you want to use the same Automatic Storage Management disk group for database files and recovery files, or you can choose to use different disk groups for each file type.

     The same choice is available to you if you use Database Configuration Assistant after the installation to create a database.

   • If you select an installation method that runs Database Configuration Assistant in noninteractive mode, then you must use the same Automatic Storage Management disk group for database files and recovery files.

2. Choose the Automatic Storage Management redundancy level that you want to use for the Automatic Storage Management disk group.

   The redundancy level that you choose for the Automatic Storage Management disk group determines how Automatic Storage Management mirrors files in the disk group and determines the number of disks and amount of disk space that you require, as follows:

   • External redundancy

     An external redundancy disk group requires a minimum of one disk device. The effective disk space in an external redundancy disk group is the sum of the disk space in all of its devices.

     Because Automatic Storage Management does not mirror data in an external redundancy disk group, Oracle recommends that you use only RAID or similar devices that provide their own data protection mechanisms as disk devices in this type of disk group.

   • Normal redundancy

     In a normal redundancy disk group, Automatic Storage Management uses two-way mirroring by default, to increase performance and reliability. A normal redundancy disk group requires a minimum of two disk devices (or two failure groups). The effective disk space in a normal redundancy disk group is half the sum of the disk space in all of its devices.

     For most installations, Oracle recommends that you select normal redundancy disk groups.

   • High redundancy

     In a high redundancy disk group, Automatic Storage Management uses three-way mirroring to increase performance and provide the highest level of reliability. A high redundancy disk group requires a minimum of three disk devices (or three failure groups). The effective disk space in a high redundancy disk group is one-third the sum of the disk space in all of its devices.

     While high redundancy disk groups do provide a high level of data protection, you must consider the greater cost of additional storage devices before deciding to select high redundancy disk groups.

3. Determine the total amount of disk space that you require for the database files and recovery files.

   Use the following table to determine the minimum number of disks and the minimum disk space requirements for the installation:

   Redundancy Level	Minimum Number of Disks	Database Files	Recovery Files	Both File Types
   External	1	1.15 GB	2.3 GB	3.45 GB
   Normal	2	2.3 GB	4.6 GB	6.9 GB
   High	3	3.45 GB	6.9 GB	10.35 GB

   
   

   For RAC installations, you must also add additional disk space for the Automatic Storage Management metadata. You can use the following formula to calculate the additional disk space requirements (in MB):

   15 + (2 * number_of_disks) + (126 * number_of_Automatic_Storage_Management_instances)

   For example, for a four-node RAC installation, using three disks in a high redundancy disk group, you require an additional 525 MB of disk space:

   15 + (2 * 3) + (126 * 4) = 525

   If an Automatic Storage Management instance is already running on the system, then you can use an existing disk group to meet these storage requirements. If necessary, you can add disks to an existing disk group during the installation.

   The following section describes how to identify existing disk groups and determine the free disk space that they contain.

4. Optionally, identify failure groups for the Automatic Storage Management disk group devices.

   
   

   Note: You need to complete this step only if you intend to use an installation method that runs Database Configuration Assistant in interactive mode, for example, if you intend to choose the Custom installation type or the Advanced database configuration option. Other installation types do not enable you to specify failure groups.

   
   

   If you intend to use a normal or high redundancy disk group, then you can further protect your database against hardware failure by associating a set of disk devices in a custom failure group. By default, each device comprises its own failure group. However, if two disk devices in a normal redundancy disk group are attached to the same SCSI controller, then the disk group becomes unavailable if the controller fails. The controller in this example is a single point of failure.

   To protect against failures of this type, you could use two SCSI controllers, each with two disks, and define a failure group for the disks attached to each controller. This configuration would enable the disk group to tolerate the failure of one SCSI controller.

   
   

   Note: If you define custom failure groups, then you must specify a minimum of two failure groups for normal redundancy disk groups and three failure groups for high redundancy disk groups.

   
   

5. If you are sure that a suitable disk group does not exist on the system, then install or identify appropriate disk devices to add to a new disk group. Use the following guidelines when identifying appropriate disk devices:

   • All of the devices in an Automatic Storage Management disk group should be the same size and have the same performance characteristics.

   • Do not specify more than one partition on a single physical disk as a disk group device. Automatic Storage Management expects each disk group device to be on a separate physical disk.

   • Although you can specify a logical volume as a device in an Automatic Storage Management disk group, Oracle does not recommend their use. Logical volume managers can hide the physical disk architecture, preventing Automatic Storage Management from optimizing I/O across the physical devices.

   
   

   See Also: The "Configuring Disks for Automatic Storage Management" section for information about completing this task

   
   

3.5.2 Using an Existing Automatic Storage Management Disk Group

If you want to store either database or recovery files in an existing Automatic Storage Management disk group, then you have the following choices, depending on the installation method that you select:

• If you select an installation method that runs Database Configuration Assistant in interactive mode (for example, by choosing the Advanced database configuration option), then you can decide whether you want to create a disk group, or use an existing one.

  The same choice is available to you if you use Database Configuration Assistant after the installation to create a database.

• If you select an installation method that runs Database Configuration Assistant in noninteractive mode, then you must choose an existing disk group for the new database; you cannot create a disk group. However, you can add disk devices to an existing disk group if it has insufficient free space for your requirements.

To determine whether an existing Automatic Storage Management disk group exists, or to determine whether there is sufficient disk space in a disk group, you can use Oracle Enterprise Manager Grid Control or Database Control. Alternatively, you can use the following procedure:

1. View the contents of the oratab file to determine whether an Automatic Storage Management instance is configured on the system:

   # more /etc/oratab
   
   

   If an Automatic Storage Management instance is configured on the system, then the oratab file should contain a line similar to the following:

   +ASM2:oracle_home_path
   
   

   In this example, +ASM2 is the system identifier (SID) of the Automatic Storage Management instance, with the node number appended, and oracle_home_path is the Oracle home directory where it is installed. By convention, the SID for an Automatic Storage Management instance begins with a plus sign.

2. Set the ORACLE_SID and ORACLE_HOME environment variables to specify the appropriate values for the Automatic Storage Management instance that you want to use.

3. Connect to the Automatic Storage Management instance as the SYS user with SYSDBA privilege and start the instance if necessary:

   # $ORACLE_HOME/bin/sqlplus "SYS/SYS_password as SYSDBA"
   SQL> STARTUP
   
   

4. Enter the following command to view the existing disk groups, their redundancy level, and the amount of free disk space in each one:

   SQL> SELECT NAME,TYPE,TOTAL_MB,FREE_MB FROM V$ASM_DISKGROUP;
   
   

5. From the output, identify a disk group with the appropriate redundancy level and note the free space that it contains.

6. If necessary, install or identify the additional disk devices required to meet the storage requirements listed in the previous section.

   
   

   Note: If you are adding devices to an existing disk group, then Oracle recommends that you use devices that have the same size and performance characteristics as the existing devices in that disk group.

   
   

3.5.3 Configuring Disks for Automatic Storage Management

To configure disks for use with ASM on HP-UX, follow these steps:

1. If necessary, install the shared disks that you intend to use for the ASM disk group.

2. To make sure that the disks are available, enter the following command on every node:

   # /usr/sbin/ioscan -fun -C disk
   
   

   The output from this command is similar to the following:

   Class  I  H/W Path    Driver S/W State   H/W Type     Description
   ==========================================================================
   disk    0  0/0/1/0.6.0 sdisk  CLAIMED     DEVICE       HP   DVD-ROM 6x/32x
                          /dev/dsk/c0t6d0   /dev/rdsk/c0t6d0
   disk    1  0/0/1/1.2.0 sdisk  CLAIMED     DEVICE      SEAGATE ST39103LC
                          /dev/dsk/c1t2d0   /dev/rdsk/c1t2d0
   
   

   This command displays information about each disk attached to the system, including the block device name (/dev/dsk/cxtydz) and the character raw device name (/dev/rdsk/cxtydz).

3. If the ioscan command does not display device name information for a device that you want to use, enter the following command to install the special device files for any new devices:

   # /usr/sbin/insf -e
   
   

4. For each disk that you want to add to a disk group, enter the following command on any node to verify that it is not already part of an LVM volume group:

   # /sbin/pvdisplay /dev/dsk/cxtydz
   
   

   If this command displays volume group information, the disk is already part of a volume group. The disks that you choose must not be part of an LVM volume group.

   
   

   Note: If you are using different volume management software, for example VERITAS Volume Manager, refer to the appropriate documentation for information about verifying that a disk is not in use.

   
   

5. Enter commands similar to the following on every node to change the owner, group, and permissions on the character raw device file for each disk that you want to add to a disk group:

   # chown oracle:dba /dev/rdsk/cxtydz
   # chmod 660 /dev/rdsk/cxtydz
   
   

   
   

   Note: If you are using a multi-pathing disk driver with ASM, make sure that you set the permissions only on the correct logical device name for the disk. If the nodes are configured differently, the device name for a particular device might be different on some nodes. Make sure that you specify the correct device names on each node.

   
   

6. If you also want to use raw devices for storage, refer to the next section, "Configuring Disks for Database Files on Raw Devices".

3.6.1 Identifying Partitions and Configuring Raw Devices for Database Files

Table 3-3 lists the number and size of the raw disk devices that you must configure for database files.

dbname_system_raw_500m

dbname_sysaux_raw_800m

dbname_undotbsn_raw_500m

dbname_temp_raw_250m

dbname_example_raw_160m

dbname_users_raw_120m

dbname_redon_m_raw_120m

dbname_control{1|2}_raw_110m

dbname_spfile_raw_5m

dbname_pwdfile_raw_5m

1. If you intend to use raw disk devices for database file storage, then choose a name for the database that you want to create.

   The name that you choose must start with a letter and have no more than four characters, for example, orcl.

2. Identify or configure the required disk devices.

   The disk devices must be shared on all of the cluster nodes.

3. To ensure that the disks are available, enter the following command on every node:

   # /usr/sbin/ioscan -fun -C disk
   
   

   The output from this command is similar to the following:

   Class  I  H/W Path    Driver S/W State   H/W Type     Description
   ==========================================================================
   disk    0  0/0/1/0.6.0 sdisk  CLAIMED     DEVICE       HP   DVD-ROM 6x/32x
                          /dev/dsk/c0t6d0   /dev/rdsk/c0t6d0
   disk    1  0/0/1/1.2.0 sdisk  CLAIMED     DEVICE      SEAGATE ST39103LC
                          /dev/dsk/c1t2d0   /dev/rdsk/c1t2d0
   
   

   This command displays information about each disk attached to the system, including the block device name (/dev/dsk/cxtydz) and the character raw device name (/dev/rdsk/cxtydz).

4. If the ioscan command does not display device name information for a device that you want to use, then enter the following command to install the special device files for any new devices:

   # /usr/sbin/insf -e
   
   

5. For each disk that you want to use, enter the following command on any node to verify that it is not already part of an LVM volume group:

   # /sbin/pvdisplay /dev/dsk/cxtydz
   
   

   If this command displays volume group information, then the disk is already part of a volume group. The disks that you choose must not be part of an LVM volume group.

   
   

   Note: If you are using different volume management software, for example VERITAS Volume Manager, then refer to the appropriate documentation for information about verifying that a disk is not in use.

   
   

6. If the ioscan command shows different device names for the same device on any node, then:

   1. Change directory to the /dev/rdsk directory.

   2. Enter the following command to list the raw disk device names and their associated major and minor numbers:

      # ls -la
      
      

      The output from this command is similar to the following for each disk device:

      crw-r--r--   1 bin        sys        188 0x032000 Nov  4  2003 c3t2d0
      
      

      In this example, 188 is the device major number and 0x32000 is the device minor number.

   3. Enter the following command to create a new device file for the disk that you want to use, specifying the same major and minor number as the existing device file:

      
      

      Note: Oracle recommends that you use the alternative device file names shown in the previous table.

      
      

      # mknod ora_ocr_raw_100m c 188 0x032000
      
      

   4. Repeat these steps on each node, specifying the correct major and minor numbers for the new device files on each node.

7. Enter commands similar to the following on every node to change the owner, group, and permissions on the character raw device file for each disk device that you want to use:

   
   

   Note: If you are using a multi-pathing disk driver with Automatic Storage Management, then ensure that you set the permissions only on the correct logical device name for the disk. If you created an alternative device file for the device, then set the permissions on that device file.

   
   

   • OCR:

     # chown root:oinstall /dev/rdsk/cxtydz
     # chmod 640 /dev/rdsk/cxtydz
     
     

   • Oracle Clusterware voting disk or database files:

     # chown oracle:dba /dev/rdsk/cxtydz
     # chmod 660 /dev/rdsk/cxtydz
     
     

8. If you are using raw disk devices for database files, then follow these steps to create the Oracle Database Configuration Assistant raw device mapping file:

   
   

   Note: You must complete this procedure only if you are using raw devices for database files. The Oracle Database Configuration Assistant raw device mapping file enables Oracle Database Configuration Assistant to identify the appropriate raw disk device for each database file. You do not specify the raw devices for the Oracle Clusterware files in the Oracle Database Configuration Assistant raw device mapping file.

   
   

   1. Set the ORACLE_BASE environment variable to specify the Oracle base directory that you identified or created previously:

      • Bourne, Bash, or Korn shell:

        $ ORACLE_BASE=/u01/app/oracle ; export ORACLE_BASE
        
        

      • C shell:

        % setenv ORACLE_BASE /u01/app/oracle
        
        

   2. Create a database file subdirectory under the Oracle base directory and set the appropriate owner, group, and permissions on it:

      # mkdir -p $ORACLE_BASE/oradata/dbname
      # chown -R oracle:oinstall $ORACLE_BASE/oradata
      # chmod -R 775 $ORACLE_BASE/oradata
      
      

      In this example, dbname is the name of the database that you chose previously.

   3. Change directory to the $ORACLE_BASE/oradata/dbname directory.

   4. Using any text editor, create a text file similar to the following that identifies the disk device file name associated with each database file.

      Oracle recommends that you use a file name similar to dbname_raw.conf for this file.

      
      

      Note: The following example shows a sample mapping file for a two-instance RAC cluster. Some of the devices use alternative disk device file names. Ensure that the device file name that you specify identifies the same disk device on all nodes.

      
      

      system=/dev/rdsk/c2t1d1
      sysaux=/dev/rdsk/c2t1d2
      example=/dev/rdsk/c2t1d3
      users=/dev/rdsk/c2t1d4
      temp=/dev/rdsk/c2t1d5
      undotbs1=/dev/rdsk/c2t1d6
      undotbs2=/dev/rdsk/c2t1d7
      redo1_1=/dev/rdsk/c2t1d8
      redo1_2=/dev/rdsk/c2t1d9
      redo2_1=/dev/rdsk/c2t1d10
      redo2_2=/dev/rdsk/c2t1d11
      control1=/dev/rdsk/c2t1d12
      control2=/dev/rdsk/c2t1d13
      spfile=/dev/rdsk/dbname_spfile_raw_5m
      pwdfile=/dev/rdsk/dbname_pwdfile_raw_5m
      
      

      In this example, dbname is the name of the database.

      Use the following guidelines when creating or editing this file:

      • Each line in the file must have the following format:

        database_object_identifier=device_file_name
        
        

        The alternative device file names suggested in the previous table include the database object identifier that you must use in this mapping file. For example, in the following alternative disk device file name, redo1_1 is the database object identifier:

        rac_redo1_1_raw_120m
        
        

      • For a RAC database, the file must specify one automatic undo tablespace datafile (undotbsn) and two redo log files (redon_1, redon_2) for each instance.

      • Specify at least two control files (control1, control2).

      • To use manual instead of automatic undo management, specify a single RBS tablespace datafile (rbs) instead of the automatic undo management tablespace data files.

   5. Save the file and note the file name that you specified.

   6. When you are configuring the oracle user's environment later in this chapter, set the DBCA_RAW_CONFIG environment variable to specify the full path to this file.

9. When you are installing Oracle Clusterware, you must enter the paths to the appropriate device files when prompted for the path of the OCR and Oracle Clusterware voting disk, for example:

   /dev/rdsk/cxtydz
   
   

3.6.2 Creating the Oracle Database Configuration Assistant Raw Device Mapping File

To enable Oracle Database Configuration Assistant to identify the appropriate raw device for each database file, you must create a raw device mapping file, as follows:

1. Set the ORACLE_BASE environment variable to specify the Oracle base directory that you identified or created previously:

   • Bourne, Bash, or Korn shell:

     $ ORACLE_BASE=/u01/app/oracle ; export ORACLE_BASE
     
     

   • C shell:

     % setenv ORACLE_BASE /u01/app/oracle
     
     

2. Create a database file subdirectory under the Oracle base directory and set the appropriate owner, group, and permissions on it:

   # mkdir -p $ORACLE_BASE/oradata/dbname
   # chown -R oracle:oinstall $ORACLE_BASE/oradata
   # chmod -R 775 $ORACLE_BASE/oradata
   
   

   In this example, dbname is the name of the database that you chose previously.

3. Change directory to the $ORACLE_BASE/oradata/dbname directory.

4. Enter a command similar to the following to create a text file that you can use to create the raw device mapping file:

   # find /dev/vg_name -user oracle -name 'r*' -print > dbname_raw.conf
   
   

5. Edit the dbname_raw.conf file in any text editor to create a file similar to the following:

   
   

   Note: The following example shows a sample mapping file for a two-instance RAC cluster.

   
   

   system=/dev/vg_name/rdbname_system_raw_500m
   sysaux=/dev/vg_name/rdbname_sysaux_raw_800m
   example=/dev/vg_name/rdbname_example_raw_160m
   users=/dev/vg_name/rdbname_users_raw_120m
   temp=/dev/vg_name/rdbname_temp_raw_250m
   undotbs1=/dev/vg_name/rdbname_undotbs1_raw_500m
   undotbs2=/dev/vg_name/rdbname_undotbs2_raw_500m
   redo1_1=/dev/vg_name/rdbname_redo1_1_raw_120m
   redo1_2=/dev/vg_name/rdbname_redo1_2_raw_120m
   redo2_1=/dev/vg_name/rdbname_redo2_1_raw_120m
   redo2_2=/dev/vg_name/rdbname_redo2_2_raw_120m
   control1=/dev/vg_name/rdbname_control1_raw_110m
   control2=/dev/vg_name/rdbname_control2_raw_110m
   spfile=/dev/vg_name/rdbname_spfile_raw_5m
   pwdfile=/dev/vg_name/rdbname_pwdfile_raw_5m
   
   

   In this example:

   • vg_name is the name of the volume group

   • dbname is the name of the database

   Use the following guidelines when creating or editing this file:

   • Each line in the file must have the following format:

     database_object_identifier=logical_volume
     
     

     The logical volume names suggested in this manual include the database object identifier that you must use in this mapping file. For example, in the following logical volume name, redo1_1 is the database object identifier:

     /dev/oracle_vg/rrac_redo1_1_raw_120m
     
     

   • The file must specify one automatic undo tablespace datafile (undotbsn) and two redo log files (redon_1, redon_2) for each instance.

   • Specify at least two control files (control1, control2).

   • To use manual instead of automatic undo management, specify a single RBS tablespace datafile (rbs) instead of the automatic undo management tablespace data files.

   • Save the file and note the file name that you specified.

   • When you are configuring the oracle user's environment later in this chapter, set the DBCA_RAW_CONFIG environment variable to specify the full path to this file.