Creating Node-Specific Files and Directories for a Shared File System

To simplify the maintenance of your Oracle installation, you can install the Oracle binary files and Oracle configuration files on a shared file system. The following shared file systems are supported:

• The Sun StorEdge QFS shared file system

• The cluster file system

• A file system on a Network Appliance NAS device

When Oracle software is installed on a shared file system, all the files in the directory that the ORACLE_HOME environment variable specifies are accessible by all cluster nodes. However, some Oracle files and directories must maintain node-specific information.

If you install Oracle software on a shared file system, you must create local copies of files and directories that must maintain node-specific information. To ensure that these files and directories are accessible by all cluster nodes, use a symbolic link whose target is a file or a directory on a file system that is local to a node. Such a file system is not part of the shared file system.

To use a symbolic link for this purpose, you must allocate an area on a local file system. To enable Oracle applications to create symbolic links to files in this area, the applications must be able to access files in this area. Because the symbolic links reside on the shared file system, all references to the links from all nodes are the same. Therefore, all nodes must have the same namespace for the area on the local file system.

Creating a Node-Specific Directory for a Shared File System

Perform this procedure for each directory that is to maintain node-specific information. The following directories are typically required to maintain node-specific information:

• $ORACLE_HOME/rdbms/audit

• $ORACLE_HOME/rdbms/log

• $ORACLE_HOME/network/agent

• $ORACLE_HOME/network/log

• $ORACLE_HOME/network/trace

• $ORACLE_HOME/srvm/log

• $ORACLE_HOME/apache

For information about other directories that might be required to maintain node-specific information, see your Oracle documentation.

How to Create a Node-Specific Directory for a Shared File System

Steps

1. On each cluster node, create the local directory that is to maintain node-specific information.

   Ensure that the local directory structure that you create matches the global directory structure that contains the node-specific information. For example, the global directory /global/oracle/network/agent might contain node-specific information that you require to be stored locally under the /local directory. In this situation, you would create a directory that is named /local/oracle/network/agent.

   # mkdir -p local-dir

   -p

   Specifies that all nonexistent parent directories are created first

   local-dir

   Specifies the full path name of the directory that you are creating

2. On each cluster node, make a local copy of the global directory that is to maintain node-specific information.

   Ensure that the local copy of the node-specific information is contained in the local directory that you created in Step 1.

   # cp -pr global-dir local-dir-parent

   -p

   Specifies that the owner, group, permissions modes, modification time, access time, and access control lists are preserved.

   -r

   Specifies that the directory and all its files, including any subdirectories and their files, are copied.

   global-dir

   Specifies the full path of the global directory that you are copying. This directory resides on the shared file system under the directory that the ORACLE_HOME environment variable specifies.

   local-dir-parent

   Specifies the directory on the local node that is to contain the local copy. This directory is the parent directory of the directory that you created in Step 1.

3. Replace the global directory that you copied in Step 2 with a symbolic link to the local copy of the global directory.

   1. From any cluster node, remove the global directory that you copied in Step 2.

      # rm -r global-dir

      -r

      Specifies that the directory and all its files, including any subdirectories and their files, are removed.

      global-dir

      Specifies the file name and full path of the global directory that you are removing. This directory is the global directory that you copied in Step 2.

   2. From any cluster node, create a symbolic link from the local copy of the directory to the global directory that you removed in Step a.

      # ln -s local-dir global-dir

      -s

      Specifies that the link is a symbolic link

      local-dir

      Specifies that the local directory that you created in Step 1 is the source of the link

      global-dir

      Specifies that the global directory that you removed in Step a is the target of the link

Example 3–1 Creating Node-Specific Directories

This example shows the sequence of operations that is required to create node-specific directories on a two-node cluster. This cluster is configured as follows:

• The ORACLE_HOME environment variable specifies the /global/oracle directory.

• The local file system on each node is located under the /local directory.

The following operations are performed on each node:

1. To create the required directories on the local file system, the following commands are run:

   # mkdir -p /local/oracle/network/agent

   # mkdir -p /local/oracle/network/log

   # mkdir -p /local/oracle/network/trace

   # mkdir -p /local/oracle/srvm/log

   # mkdir -p /local/oracle/apache

2. To make local copies of the global directories that are to maintain node-specific information, the following commands are run:

   # cp -pr $ORACLE_HOME/network/agent /local/oracle/network/.

   # cp -pr $ORACLE_HOME/network/log /local/oracle/network/.

   # cp -pr $ORACLE_HOME/network/trace /local/oracle/network/.

   # cp -pr $ORACLE_HOME/srvm/log /local/oracle/srvm/.

   # cp -pr $ORACLE_HOME/apache /local/oracle/.

The following operations are performed on only one node:

1. To remove the global directories, the following commands are run:

   # rm -r $ORACLE_HOME/network/agent

   # rm -r $ORACLE_HOME/network/log

   # rm -r $ORACLE_HOME/network/trace

   # rm -r $ORACLE_HOME/srvm/log

   # rm -r $ORACLE_HOME/apache

2. To create symbolic links from the local directories to their corresponding global directories, the following commands are run:

   # ln -s /local/oracle/network/agent $ORACLE_HOME/network/agent

   # ln -s /local/oracle/network/log $ORACLE_HOME/network/log

   # ln -s /local/oracle/network/trace $ORACLE_HOME/network/trace

   # ln -s /local/oracle/srvm/log $ORACLE_HOME/srvm/log

   # ln -s /local/oracle/apache $ORACLE_HOME/apache

Creating a Node-Specific File for a Shared File System

Perform this procedure for each file that is to maintain node-specific information. The following files are typically required to maintain node-specific information:

• $ORACLE_HOME/network/admin/snmp_ro.ora

• $ORACLE_HOME/network/admin/snmp_rw.ora

For information about other files that might be required to maintain node-specific information, see your Oracle documentation.

How to Create a Node-Specific File for a Shared File System

Steps

1. On each cluster node, create the local directory that will contain the file that is to maintain node-specific information.

   # mkdir -p local-dir

   -p

   Specifies that all nonexistent parent directories are created first

   local-dir

   Specifies the full path name of the directory that you are creating

2. On each cluster node, make a local copy of the global file that is to maintain node-specific information.

   # cp -p global-file local-dir

   -p

   Specifies that the owner, group, permissions modes, modification time, access time, and access control lists are preserved.

   global-file

   Specifies the file name and full path of the global file that you are copying. This file was installed on the shared file system under the directory that the ORACLE_HOME environment variable specifies.

   local-dir

   Specifies the directory that is to contain the local copy of the file. This directory is the directory that you created in Step 1.

3. Replace the global file that you copied in Step 2 with a symbolic link to the local copy of the file.

   1. From any cluster node, remove the global file that you copied in Step 2.

      # rm global-file

      global-file

      Specifies the file name and full path of the global file that you are removing. This file is the global file that you copied in Step 2.

   2. From any cluster node, create a symbolic link from the local copy of the file to the global file that you removed in Step a.

      # ln -s local-file global-file

      -s

      Specifies that the link is a symbolic link

      local-file

      Specifies that the file that you copied in Step 2 is the source of the link

      global-file

      Specifies that the global version of the file that you removed in Step a is the target of the link

Example 3–2 Creating Node-Specific Files

This example shows the sequence of operations that is required to create node-specific files on a two-node cluster. This cluster is configured as follows:

• The ORACLE_HOME environment variable specifies the /global/oracle directory.

• The local file system on each node is located under the /local directory.

The following operations are performed on each node:

1. To create the local directory that will contain the files that are to maintain node-specific information, the following command is run:

   # mkdir -p /local/oracle/network/admin

2. To make a local copy of the global files that are to maintain node-specific information, the following commands are run:

   # cp -p $ORACLE_HOME/network/admin/snmp_ro.ora \ /local/oracle/network/admin/.

   # cp -p $ORACLE_HOME/network/admin/snmp_rw.ora \ /local/oracle/network/admin/.

The following operations are performed on only one node:

1. To remove the global files, the following commands are run:

   # rm $ORACLE_HOME/network/admin/snmp_ro.ora

   # rm $ORACLE_HOME/network/admin/snmp_rw.ora

2. To create symbolic links from the local copies of the files to their corresponding global files, the following commands are run:

   # ln -s /local/oracle/network/admin/snmp_ro.ora \ $ORACLE_HOME/network/admin/snmp_rw.ora

   # ln -s /local/oracle/network/admin/snmp_rw.ora \ $ORACLE_HOME/network/admin/snmp_rw.ora

Next Steps

Go to Automating the Startup and Shutdown of Oracle Real Application Clusters Database Instances.