Oracle^® Business Intelligence Server Administration Guide > Clustering Oracle BI Servers >

Components of the Cluster Server

In a clustering environment, the following components are available:

• Two Cluster Controllers. For more information, see About Cluster Controllers.
• One or more servers. For more information, see About Servers Used in Clustering.
• One or more Schedulers. There can only be one active Scheduler (only one Scheduler running jobs). For more information, see About Schedulers Used in Clustering.
• Cluster Manager. A utility in the Administration Tool.
• Repository Publishing Directory. This directory is shared by all Oracle BI Servers participating in a cluster. It holds the master copies of repositories edited in online mode. The clustered Oracle BI Servers examine this directory upon startup for any repository changes. The directory typically resides on a shared file system visible to all servers in the cluster. You must set up the following access to this publishing directory:
  • The master server must have read and write access.
  • All slave servers must have read access.

    In the NQSConfig.INI file, the REPOSITORY_PUBLISHING_DIRECTORY parameter specifies the location of the repository publishing directory.

About Cluster Controllers

The following are the types of Cluster Controllers with their descriptions:

• Primary Cluster Controller. The role of the primary Cluster Controller is to monitor the operation of the servers and Schedulers in the cluster and to assign sessions within the cluster. The primary Cluster Controller can reside on the same machine as an Oracle BI Server in the cluster or on another machine that is on the same subnet as the cluster. A machine can host one Oracle BI Server, one Cluster Controller, one Scheduler, or one of each. The primary controller also determines the active Scheduler in the cluster and notifies Scheduler instances when the active instance changes.

  In the NQClusterConfig.INI file, the parameter PRIMARY_CONTROLLER specifies the machine that hosts the primary Cluster Controller.

• Secondary Cluster Controller. The secondary Cluster Controller assumes the role of the primary Cluster Controller if the primary is unavailable. The secondary Cluster Controller can reside on the same machine as an Oracle BI Server in the cluster or on another machine that is on the same subnet as the cluster.

  In the NQClusterConfig.INI file, the parameter SECONDARY_CONTROLLER specifies the machine that will host the secondary Cluster Controller. It must be different from the machine that hosts the primary Cluster Controller. Specifying a secondary Cluster Controller is optional. However, if the primary Cluster Controller is unavailable and the secondary Cluster Controller has not been configured, the cluster will not operate.

  NOTE:  In the NQClusterConfig.ini file, you must not use fully-qualified machine names because all servers are required to run on the same LAN. Use the syntax machinename not machinename.domain.

About Servers Used in Clustering

The following are descriptions of the types of servers used in clustering:

• Master server. A master server is a clustered Oracle BI Server to which the Administration Tool connects for online repository changes. In the NQClusterConfig.INI file, the parameter MASTER_SERVER specifies the Oracle BI Server that functions as the master server.
• Slave server. A slave server is a clustered Oracle BI Server that does not allow online repository changes. It is used in load balancing of ODBC sessions to the Oracle BI Server cluster. If the master server is ever down, the Administration Tool will connect to an available slave server, but in read-only mode.

About Schedulers Used in Clustering

The following are the types of Schedulers used in clustering with their descriptions:

• Active Scheduler. An active Scheduler is a clustered Oracle BI Scheduler instance which actively processes Scheduler jobs. The Cluster Controller determines the active instance at run time and notifies the Scheduler cluster of this instance.
• Inactive Scheduler. An inactive Scheduler is a clustered Oracle BI Scheduler instance which is not actively processing Scheduler jobs but is ready to take over in the event of an active Scheduler failure. An inactive scheduler is idle at all other times.

About the Cluster Manager

The Cluster Manager is a utility that is available in the Administration Tool when a repository is open in online mode. It allows the Oracle BI Administrator to monitor and manage the operations and activities of the cluster.

You cannot start, stop, or restart services from the Cluster Manager. Use the mechanism provided with your operating system for stopping and restarting an Oracle BI service. For Oracle BI Scheduler instances, the only option from the right-click menu is Activate.

For Oracle BI Server instances, the only options from the right-click menu are Quiesce (stop taking new sessions) or Enable (take new sessions). If an Oracle BI Server instance is running, you can select Quiesce. If it is queisced, you can select Enable.