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A service can span one or more instances of an Oracle database in a cluster. Available Demonstrations To illustrate the major concepts that were briefly introduced in this lesson. RAC Administration 1. Objectives After completing this lesson. The enhancements include: The first phase installs Oracle Clusterware. Oracle Clusterware provides high-availability components and can also interact with vendor clusterware. The installation also enables you to configure services for your RAC environment.
If you have a previous Oracle cluster database version. Installation Utilities: The Oracle Database 11g installation process provides a single-system image. DBUA creates a restore script to restore the database. Oracle RAC 11g Installation: Outline 1. Perform ASM installation. Perform Oracle Clusterware installation. This is considered a best practice. Complete postinstallation tasks. You must perform step-by-step tasks for hardware and software verification. Make sure that your cluster hardware is functioning normally before you begin this step.
Oracle Clusterware must be installed using OUI. Complete preinstallation tasks: After Oracle Clusterware has been successfully installed and tested. You must install the operating system patches required by the cluster database. The remainder of this lesson provides the necessary knowledge to complete these tasks successfully. Before the installation can begin in earnest.
Perform cluster database creation.
Failure to do so results in an aborted or nonoperative installation. Perform Oracle Database 11g software installation. Install EM agent on cluster nodes if using Grid Control. After the database has been created. In UNIX systems. This means that the administrative privileges user account and password must be the same on all nodes.
On Oracle RAC systems. You do not need a separate account. OUI creates and sets startup and shutdown services at installation time. Preinstallation Tasks Check system requirements. Others are specific to Oracle RAC 11g. Create groups and users. Check kernel parameters. Attention to details here simplifies the rest of the installation process. Some of these tasks are common to all Oracle database installations and should be familiar to you. Perform cluster setup.
Preinstallation Tasks Several tasks must be completed before the Oracle Clusterware and Oracle Database 11g software can be installed. Check software requirements. Failure to complete these tasks can certainly affect your installation and possibly force you to restart the process from the beginning. On systems with 2 GB or more of memory.
To determine the amount of physical memory. The df command can be used to check for the availability of the required disk space. Hardware Requirements The system must meet the following minimum hardware requirements: To determine the size of the configured swap space. The virtual IP address must be in the same subnet as the associated public interface.
Before starting the installation. For the public network. After installation. For a more complete list of supported protocols. If a node fails. For the private network. Network Requirements Each node must have at least two network adapters: For the private IP address and optional host name for each private interface.
Gigabit Ethernet or an equivalent is recommended. Oracle recommends that you use private network IP addresses for these interfaces.
When this occurs: The slide shows you the connect case with and without VIP. In the case of SQL. When a node fails. Without using VIPs. This means that when the client issues SQL to the node that is now down 3. As a result.
For directly connected clients. In the case of connect. This results in the clients getting errors immediately. On the basis of this testing and extensive experience with production customer deployments.
In addition to UDP. Best practices for UDP include: Your interconnect must be certified by Oracle for your platform. You should also have a Web browser to view online documentation.
Hyper Messaging protocol. Oracle Universal Installer OUI performs checks on your system to verify that it meets the Linux package requirements of the cluster database and related services. To determine whether the required packages are installed. Package Requirements Depending on the products that you intend to install. To ensure that these checks succeed. The nobody user must own the external jobs extjob executable after the installation.
This user owns all the software installed during the installation. If you want to specify a group name other than the default dba group. OUI prompts you to specify the name of this group.
You must verify that the unprivileged user named nobody exists on the system. This group owns the Oracle inventory.
The usual name chosen for this user is oracle. You must create the oracle user the first time you install the Oracle database software on the system. You must create the dba group the first time you install the Oracle database software on the system.
This user must have the Oracle Inventory group as its primary group. It identifies the UNIX users that have database administrative privileges. To configure the environment. Use the df -k command to identify a suitable file system with sufficient free space. Make sure that the oracle user and the oinstall group can write to the directory.
The maximum number of open file descriptors should be PAM is a system of libraries that handle the authentication tasks of applications services on the system. The maximum number of processes available to a single user must not be less than User Shell Limits To improve the performance of the software. The principal feature of the PAM approach is that the nature of the authentication is dynamically configurable.
The hard values. When prompted for the pass phrase. As the oracle user. Create the public and private keys on all nodes: Test the configuration. Configuring for Remote Installation continued 3. The first time you install the Oracle database software on a system. The Oracle inventory directory oraInventory stores the inventory of all software installed on the system. Required Directories for the Oracle Database Software You must identify five directories for the Oracle database software: It is required by.
On UNIX systems. OUI prompts you to specify the path to this directory. If you are installing the software on a local file system.
Specify a path similar to the following directory for ASM: When you run OUI. You must install Oracle Clusterware in a separate home directory. You must install different Oracle products. It is recommended that you specify a path similar to the following for the Oracle Clusterware home directory: Required Directories for the Oracle Database Software continued The Oracle Clusterware home directory is the directory where you choose to install the software for Oracle Clusterware.
The Oracle home directory is the directory where you choose to install the software for a particular Oracle product. The directory that you specify must be a subdirectory of the Oracle base directory. Because the clusterware parent directory should be owned by root. It is recommended that you specify a path similar to the following for the Oracle home directory: Linux Operating System Parameters Verify that the parameters shown in the table above are set to values greater than or equal to the recommended value shown.
Use the sysctl command to view the default values of the various parameters. For example, to view the semaphore parameters, run the following command: The values shown represent semmsl, semmns, semopm, and semmni in that order.
Kernel parameters that can be manually set include: Semaphores are grouped into semaphore sets, and SEMMSL controls the array size, or the number of semaphores that are contained per semaphore set. It should be about ten more than the maximum number of the Oracle processes. The maximum size of a shared-memory segment.
The number of shared memory identifiers. The kernel parameters shown above are recommended values only. For production database systems, it is recommended that you tune these values to optimize the performance of the system. Because they are a lot of parameters to check, you can use the Cluster Verification Utility to automatically do the verification. View the Certifications by Product section at http: Verify your high-speed interconnects.
Determine the shared storage disk option for your system:. See the Certifications by Product section at http: Verify that your cluster interconnects are functioning properly. Determine the storage option for your system, and configure the shared disk.
Oracle Clusterware requires that the OCR files and voting disk files be shared. These files could map to shared block or raw devices or exist on an OCFS volume. Verifying Cluster Setup with cluvfy The Cluster Verification Utility cluvfy enables you to perform many preinstallation and postinstallation checks at various stages of your RAC database installation.
The cluvfy utility is available in Oracle Database 11g Release 1. To check the readiness of your cluster for an Oracle Clusterware installation, run cluvfy as shown below: Node reachability check passed from node "vx". Checking user equivalence User equivalence check passed for user "oracle". Checking node connectivity Node connectivity check passed. Checking shared storage accessibility Shared storage check passed on nodes "vx,vx". Post-check for hardware and operating system setup was successful on all the nodes.
RAC Administration 1 - Click the Oracle Clusterware button and then click Next. You may accept the name or enter a new name at this time. If not, enter the location in the target destination, and click Next to continue.
You should be aware of this, and not just click through because there is a value. The parent directory of the Clusterware Home should be owned by root and writable by the install group, oinstall. Product-Specific Prerequisite Checks The installer then checks your environment to ensure that it meets the minimum requirements for an Oracle Clusterware installation.
The installer checks for the existence of critical packages and release levels, proper kernel parameter settings, network settings, and so on. If discrepancies are found, they are flagged and you are given an opportunity to correct them.
If you are sure that the flagged items will not cause a problem, it is possible to click the item and change the status to self-checked, and continue with the installation. Only do this if you are absolutely sure that no problems actually exist, otherwise correct the condition before proceeding.
When all checks complete successfully, click the Next button to proceed. You must supply the public node names. OUI displays the Cluster Configuration screen without the predefined node information. If all your nodes do not appear in the cluster nodes window. Cluster Configuration The Specify Cluster Configuration screen displays predefined node information if OUI detects that your system has vendor clusterware. Ensure that the cluster name is unique in your network. In the Cluster Name field.
Private Interconnect Enforcement The Specify Network Interface Usage screen enables you to select the network interfaces on your cluster nodes to use for internode communication.
Ensure that the network interfaces that you choose for the interconnect have enough bandwidth to support the cluster and RAC-related network traffic. A gigabit Ethernet interface is highly recommended for the private interconnect. To configure the interface for private use, click the interface name, and then click Edit. A pop-up window appears and allows you to indicate the usage for the network interfaces. In the example shown in the slide, there are three interfaces: It should be marked Do Not Use.
The eth2 interface is configured for the private interconnect and should be marked Private. When you finish, click the Next button to continue. Enter a fully qualified file name for the shared block or raw device or a shared file system file for the OCR file. If you are using an external disk mirroring scheme, click the External Redundancy option button.
You will be prompted for a single OCR file location. If no mirroring scheme is employed, click the Normal Redundancy option button. You will be prompted for two file locations. For highest availability, provide locations that exist on different disks or volumes. Click Next to continue. Voting Disk File The primary purpose of the voting disk is to help in situations where the private network communication fails.
Therefore, some of the nodes must go offline. The voting disk is used to communicate the node state information used to determine which nodes will go offline. Because the voting disk must be accessible to all nodes to accurately assess membership, the file must be stored on a shared disk location.
The voting disk can reside on a block or raw device or a cluster file system. In Oracle Database 11g Release 1, voting disk availability is improved by the configuration of multiple voting disks. If the voting disk is not mirrored, then there should be at least three voting disks configured.
Note that OUI must install the components shown in the summary window. Click the Install button. The Install screen is then displayed, informing you about the progress of the installation. During the installation, OUI first copies the software to the local node and then copies the software to the remote nodes.
The root. Run the cluvfy utility to verify the post crs installation. Make sure you run the above mentioned scripts serially on each node in the proposed order. End of Installation When the configuration scripts have been run on both nodes, the Configuration Assistants page is displayed. The Cluster Verification Utility is then run to test the viability of the new installation. When the Next button is clicked, the End of Installation screen appears. Click Exit to leave OUI.
Verifying the Oracle Clusterware Installation Before continuing with the installation of the Oracle database software, you must verify your Oracle Clusterware installation and startup mechanism. With the introduction of Oracle RAC 11g, cluster management is controlled by the evmd, ocssd, and crsd processes. Run the ps command on both nodes to make sure that the processes are running. Check the startup mechanism for Oracle Clusterware. The processes are started at run levels 3 and 5 and are started with the respawn flag.
Verifying the Oracle Clusterware Installation continued This means that if the processes abnormally terminate, they are automatically restarted. If you kill the Oracle Clusterware processes, they automatically restart or, worse, cause the node to reboot.
For this reason, stopping Oracle Clusterware by killing the processes is not recommended. If you want to stop Oracle Clusterware without resorting to shutting down the node, you should run the crsctl command: If you encounter difficulty with your Oracle Clusterware installation, it is recommended that you check the associated log files.
To do this, check the directories under the Oracle Clusterware Home: This directory contains the alert. This directory contains the log files for the CSSD. This directory contains the log files for the EVMD. When you have determined that your Oracle Clusterware installation is successful and fully functional, you may start the Oracle Database 11g software installation. Summary In this lesson. Practice 1: Overview This practice covers the following topics: RAC Administration 2.
Installing Automatic Storage Management For this installation. After Oracle Clusterware is installed. Click the Oracle Database 11g button and then click Next.
Installation Type When the Installation Type screen appears. Click the Next button to proceed.
Be sure to specify a name for your installation that reflects this. Then click the Next button to continue. Here you specify the location of your ASM home directory and installation name. Although it is possible for ASM and the database installation to reside in the same directory and use the same files. Refer to your documentation if the detailed output indicates that your clusterware is not running properly.
If OUI does not display the nodes properly. When this is done. Then return to OUI. Product-Specific Prerequisite Checks The Product-Specific Prerequisite Checks screen verifies the operating system requirements that must be met for the installation to be successful. When all tests have succeeded. The example in the slide shows the results of a completely successful test suite. The test suite results are displayed at the bottom of the screen. Any tests that fail are also reported here. After each successful check.
It is possible to bypass the errors that are flagged by selecting the check box next to the error. If you encounter any failures. When you have done this. The default value is dba for each group: Then click the Install button to proceed. After installing the files and linking the executables on the first node. You can monitor the progress of the installation on the Install screen. You may scan the installation tree to verify your choices if you like.
Summary The Summary screen appears next. OUI prompts you to execute configuration scripts on all nodes. Open a terminal window for each node listed and run the root. Execute Configuration Scripts The next screen that appears prompts you to run the root. End of Installation When the root.
Click the Exit button to quit. When the installation is finished. DBCA is used to do this quickly and accurately. Click the Select All button. ASM Configuration continued On the next screen.
You now choose the nodes on which to manage ASM. Before starting the instances. Then click Next to continue. If you require specific initialization parameter values to be set for your ASM instances. ASM Configuration continued At this stage. When you click Yes to start the listeners.
ASM Configuration continued A dialog box informs you that listeners are not running on the cluster nodes and asks if you want to start them now.
Click the OK button after providing the discovery path to your disks. On the disk group creation page. Click the Create New button to create a disk group. When you have finished creating all the necessary disk groups.
Other disk groups can also be created at this point. In the example in the slide. When you click OK. A dialog box asks if you wish to perform other operations.
Click the Oracle Database 11g button and click Next. You need to run OUI as the oracle user. For this reason. For this. Your installation options include: Selecting the Custom installation type option enables you to install only those Oracle product components that you deem necessary.
Accept the suggested name or enter your own Oracle Home name. In the Software Location section of the page The Name field is populated with a default or suggested installation name.
After entering the information. Install Location On the Install Location screen. Additional nodes that are to be part of this installation must be selected by selecting the check boxes. Note that the local node is always selected for the installation. Because OUI is node aware. Restart OUI. To do this. If you do not see all your nodes listed here. Most installation scenarios require the Cluster Installation option.
Click the Next button when you are ready to proceed with the installation. Products Prerequisite Check The Product-Specific Prerequisite Checks screen verifies the operating system requirements that must be met for the installation to be successful. These requirements include: The test suite results are displayed at the bottom of the page. This option enables you to create the database by manually invoking the DBCA at some point in time after OUI finishes installing the database software.
On this screen. If you choose to install a database. This choice provides you with more options than the standard preconfigured database models. Select the Install Software Only option. Click the Next button to continue. You may also choose to defer the database creation by clicking the Install Software Only option button.
After OUI stops. OUI copies the software first to the local node and then to the remote nodes. If you are not. During installation. If you are satisfied with the summary. Node information and space requirements can be viewed here. On the Install screen. Check Summary The Summary screen is displayed next. Review the information on this page. OUI displays a dialog box indicating that you must run the root.
Execute the root. Required Tasks Prior to Database Creation You can now set the Oracle database—related environment variables for the oracle user so that they are recognized by the DBCA during database creation: User equivalence check passed for user "oracle"..
Checking administrative privileges. Checking user equivalence.. RAC Administration Use the —pre option with the dbcfg argument to thoroughly analyze your cluster before creating your RAC database.. Group existence check passed for "dba". Membership check for user "oracle" in group "dba" [as Primary] passed.. Run the Cluster Verify Utility as the oracle user. User existence check passed for "oracle".
Your output should be similar to the following example: Pre-check for database configuration was successful.. Checking CRS health. Node connectivity check passed for subnet " CRS integrity check passed. Checks Before Database Creation continued Administrative privileges check passed. CRS health check passed. Suitable interfaces for VIP on subnet " Checking node connectivity. Practice 2: RAC Administration 3. To use Grid Control. To install the Management Agent. Click the Additional Management Agent option button to install an agent only.
Both tools are based on Enterprise Manager. The Installation page provides several install types from which to choose from. Management Agent Installation: Database Control and Grid Control. Specify Installation Type There are two management tools available for your cluster database. After starting the installation and specifying the installation location as shown in the example in the slide.
Each node must be check marked before continuing. If no problems are encountered. If all the nodes do not appear. Because you want to install the agent on all cluster nodes.
You should take care of any issues identified by the installer before continuing with the installation. The port number specified is the default port used by Grid Control. If the prerequisite check identifies no problems. Prerequisite Check and OMS Location The installer next checks the minimum requirements for the installation of the agent software.
The next screen requires you to identify the location of the Oracle management service. After you complete this step. Any deficiencies are reported. You must provide the host name and port number of an existing Grid Control console.
Do not specify an arbitrary password here. The next screen is the Summary screen. Quickly review the information for accuracy and click the Next button to continue. When this information is provided. Management Agent Installation Finish During the course of the agent installation. When the installation is complete. You are now ready to create the cluster database.
Executing the root. When the installer indicates that the agent has been installed. The first option enables you to create a database and the other option enables you to manage database creation templates. For a first-time installation. Click the Create a Database option button. Click the Oracle Real Application Clusters database option button.
The Operations screen appears. You must select the type of database that you want to install. Click the Select All button to choose all the nodes of the cluster. Because you are creating a cluster database. If all nodes do not appear. Each node must be highlighted before continuing. Node Selection The Node Selection screen is now displayed. The DBCA tool provides several predefined database types to choose from.
The templates include: A system identifier SID prefix is required. This example assumes that you have a two-node cluster. If you do not want to use the system-supplied prefix. This prefix is used to generate unique SID names for the two instances that make up the cluster database.
The global database name can be up to 30 characters in length and must begin with an alphabetical character. The name that you enter in this screen must be unique among all the global database names used in your environment. Database Identification In the Database Identification screen.
The SID prefix must begin with an alphabetical character and contain no more than 5 characters on UNIX-based systems or 61 characters on Windows-based systems.
After making your choices. You must supply a backup start time as well as operating system user credentials for this option. Grid Control can simplify database management in large. If you want to configure this. If you have Grid Control installed somewhere on your network. For small cluster environments. You can also enable daily backups here. If you want to use Grid Control to manage your database but have not yet installed and configured a Grid Control server.
You can also configure Database Control to send email notifications when alerts occur. You can use the same password for all of these privileged accounts by clicking the Use the Same Password for All Accounts option button. Enter your password in the Password field. Repeat this for each user listed in the User Name column.
You must supply passwords for the user accounts created by the DBCA when configuring your database. To initiate the creation of the required ASM instance.
Your three choices are: If an ASM instance exists on the local node. After the instance is created. If you have just created a new ASM instance. If there is no ASM instance on any of the cluster nodes. After you enter the required information. You can enter your response or click the Browse button to locate it. The file should follow the format of the example below: Because this example uses a preexisting ASM disk group.
If you have configured raw devices. When you are finished. To select a disk group. When you have made your choices. This cluster database uses Oracle-managed files. You can choose to use a standard template for file locations. If you are using ASM or cluster file system storages. When you have completed your entries. If you are using ASM and a single disk group. The size of the area defaults to megabytes.
You may also define your own variables for the file locations if you plan to use the Database Storage screen to define individual file locations. If you use a cluster file system. If more than one disk group has been created. Recovery Configuration On the Recovery Configuration screen. When finished. On the Custom Scripts tabbed page. Database Content On the Database Content screen.
The default type is Dedicated Server Mode. The parameters are grouped on four tabs: If you want to review the parameters that are not found in the four tabs. If you want to use Oracle Shared Server. You can also select the default language and the date format. On the Sizing tab. Click the Use Automatic Memory Management button. On the Connection Mode tabbed page.
Initialization Parameters On the Initialization Parameters screen. By clicking the Character Sets tab. Note that the default is 8 KB. Automatic Memory Management is the preferred memory management method and can be selected here. Java pool. Make your choice here and click Next to continue. Click Enable automatic maintenance tasks to schedule metrics collection and advisor runs using predefined maintenance windows and resource consumption models.
Security Settings and Maintenance Tasks On the Security Settings page you can choose between enhanced Oracle 11g security and the preg model which requires slightly less overhead. Database Storage Options The Database Storage screen provides full control over all aspects of database storage.
Create the Database The Creation Options screen appears next. When you are ready to proceed. Review the summary data.
Select the Create Database check box. You can choose to create the database. Monitor Progress The Progress Monitor screen appears next. By clicking the Password Management button.
In addition to informing you about how fast the database creation is taking place. It also directs you to the installation log file location. When the database creation progress reaches percent. Execute the following command: If you install other products in the same Oracle Home directory.. Postinstallation Tasks After the cluster database has been successfully created. If you require information contained in the original root. After your Oracle Database 11g RAC installation is complete and after you are sure that your system is functioning properly.
The following example shows two nodes. Check Managed Targets http: Click the Targets tab to verify that all the targets appear here. Open a browser and enter the address for your Grid Control console. Check Managed Targets Another post-installation task you should perform if you are using Grid Control is to check that all the managed nodes and their managed resources are properly registered and available. You can also convert to RAC and use a nonshared file system.
In either case. The DBCA automates the configuration of the control file attributes. Oracle Clusterware resources. If your platform supports a cluster file system. It also configures Oracle Net Services. Copy the preconfigured database image. Perform the preinstallation steps. Validate the cluster. Set up the cluster. Back up the original single-instance database. Set up and validate the cluster. On the Template Management screen. Conversion Steps 1. By default. Enter a description of the file in the Description field.
On the Location of Database Related Files screen. Use the DBCA to create a preconfigured image of your single-instance database by using the following procedure: On the Welcome screen. On the Source Database screen. On the Operations screen. On the Template Properties screen.
The DBCA generates two files: Conversion Steps continued 2. Several tasks must be completed before Oracle Clusterware and Oracle Database 11g software can be installed.
When the clusterware is installed. When you have configured all of the nodes in your cluster. Conversion Steps 2. Use the browse option to select the template location. Conversion Steps continued 5. After creating the RAC database. Conversion Steps 5. You must also replace default database files with raw devices on the Storage page.
When the DBCA exits. User Accounts Configuring Kernel Parameters Set shell limits for the oracle user Create the Oracle Inventory Directory Creating the Oracle Base Directory Stage the Oracle Software Check OS Software Requirements Prepare the shared storage for Oracle RAC Shared Storage Partition the Shared Disks Oracle Grid Infrastructure Install Grid Infrastructure Home Patching RAC Home Patching Run DBCA to create the database Introduction 1.
Overview of new concepts in 11gR2 Grid Infrastructure 1. The SCAN name eliminates the need to change clients when nodes are added to or removed from the cluster. Allocate three addresses to the SCAN name. During Oracle grid infrastructure installation, listeners are created for each of the SCAN addresses, and Oracle grid infrastructure controls which server responds to a SCAN address request. This ensures high availability.
The SCAN domain name must be unique within your corporate network. The configuration can be tested as well. Each cluster member node requires an IPMI driver installed on each node. The cluster requires a management network for IPMI. This can be a shared network, but Oracle recommends that you configure a dedicated network. If you intend to use IPMI, then you must provide an administration account username and password to provide when prompted during installation. Time sync Oracle Clusterware 11g release 2 Hangchecktimer and oprocd are replaced Oracle Clusterware 11g release 2 System Requirements 1.
Hardware Requirements -Physical memory at least 1. The amount of shared disk space is determined by the size of your database. If the public interface on one node uses the network adapter eth0, then you must configure eth0 as the public interface on all nodes.
If eth1 is the private interface name for the first node, then eth1 should be the private interface name for your second node. Every node in the cluster should be able to connect to every private network interface in the cluster. This is implemented using the Twisty Plugin which requires Java Script to be enabled on your browser. User Accounts 1. Set the password for the oracle account using the following command. Replace password with your own password.
Repeat Step 1 through Step 3 on each node in your cluster. Determine your cluster name. The cluster name should satisfy the following conditions: 1. Determine the public host name for each node in the cluster. For the public host name, use the primary host name of each node. In other words, use the name displayed by the hostname command for example: racnode1.
Determine the public virtual hostname for each node in the cluster. The virtual host name is a public node name that is used to reroute client requests sent to the node if the node is down.
The virutal hostname must meet the following requirements: -The virtual IP address and the network name must not be currently in use. Determine the private hostname for each node in the cluster.