12 Oracle GoldenGate in Clustered Environments

Learn about installing and integrating Oracle GoldenGate in a clustered environment.

For more information about installing and using Oracle GoldenGate in a cluster, see the Oracle Maximum Availability Architecture Best Practices at:

http://www.oracle.com/technetwork/database/features/availability/fusion-middleware-maa-155387.html.

Topics:

12.1 Installing Oracle GoldenGate Within a Cluster

Oracle GoldenGate can be used with any cluster-management solution that has the ability to automate failover. The Oracle Clusterware solution provides the advantage of being able to be used with or without an Oracle RAC database, which enables you to include any non-database servers that are running Oracle GoldenGate.

12.1.1 Deciding Where to Install Oracle GoldenGate Binaries and Files in the Cluster

Note:

This section is applicable to Oracle GoldenGate Classic Architectureonly.

To ensure High Availability with Oracle GoldenGate it is recommended install the Oracle GoldenGate binaries on local storage for each node in the cluster. With a local node installation it is possible to patch and upgrade the Oracle GoldenGate software on one or more nodes in the cluster without affecting the node where Oracle GoldenGate is currently running. Then at a predetermined time, Oracle GoldenGate can be switched to one of the upgraded nodes.

To enable Oracle GoldenGate to run on any of the clustered nodes there is a requirement to place certain directories on shared storage. This provides the ability of the GoldenGate processes to restart from its last known position when running on a different node in the cluster.

When running Oracle GoldenGate in this manner follow these recommendations:

  • The Oracle GoldenGate installation must have the same location path on every node.

  • At minimum, install the following directories on the shared storage to support Oracle GoldenGate recovery requirements. On UNIX or Linux, you can create symbolic links to them from the installation directory on each node.

    • br

    • dirchk

    • dirdat

    • dirbdb

    • dirprm

    These directories are among those created when you issue CREATE SUBDIRS during installation.

12.1.2 Example Oracle Cluster Storage

You will need to install at least some Oracle GoldenGate directories on shared storage. Select cluster-aware shared storage that is independent of, but available to, all nodes of the cluster. You could use any of the following example Oracle cluster storage options:

  • Oracle Database File System (DBFS) reates a standard file system interface on top of files and directories that are stored in database tables. DBFS is similar to NFS in that it provides a shared network file system that looks like a local file system and has both a server component and a client component. Because the files are stored inside the database they are protected using the database backup and recovery features, along with High Availability using Oracle Data Guard.

  • Oracle Storage Management Cluster File System is a multi-platform, scalable file system, and storage management technology that extends Oracle Automatic Storage Management functionality to provide a POSIX compatible file system.

  • Oracle ZFS - Using an Oracle ZFS Appliance that can be mounted from each node in the cluster using the NFS protocol.

12.2 Installing into a Windows Cluster

  1. Log into one of the nodes in the cluster.

  2. Choose a drive for the Oracle GoldenGate installation location. This drive must be a resource within the same cluster group that contains the database instance.

  3. Ensure that this cluster group is owned by the cluster node that you are logging into.

  4. Install Oracle GoldenGate according to Installing the Oracle GoldenGate Files.

12.3 Integrating into a Cluster

If you installed Oracle GoldenGate in a cluster, use the following steps to integrate Oracle GoldenGate within the cluster solution:

12.3.1 General Requirements in a Cluster

These instructions apply generically and may not be applicable to your specific cluster system.

You must meet the following requirements when integration Oracle GoldenGate into a cluster:

  1. Register the Oracle GoldenGate Manager process (and only Manager) as a cluster-managed resource as you would any other application. Manager must be the only Oracle GoldenGate process that the cluster-management software starts and stops, because it is the parent process that manages all other processes.

  2. If the cluster uses a virtual IP address, you may need to obtain an available fixed IP address for the Manager process. The VIP must be an available IP address on the public subnet and cannot be determined through DHCP. In the parameter files of the Extract data pumps, specify the VIP of the remote Manager as the input value of the RMTHOST parameter. Other Oracle GoldenGate products that access Manager also should use the VIP.

  3. Make certain that all nodes in the cluster have synchronized system clocks. The clocks must be synchronized with the clock on the system where Extract is executed. Oracle GoldenGate compares the time of the local system to the commit timestamps to make critical decisions. For information about synchronizing system clocks, consult your system administrator.

  4. When you configure Manager, add the AUTOSTART and AUTORESTART parameters so that Manager starts the replication processes automatically. You can, when needed, control Extract, Replicat, and other Oracle GoldenGate processes from within the Oracle GoldenGate user interfaces.

  5. Mount the shared drive on one node only. This prevents processes from being started on another node. Use the same mount point on all nodes.

  6. Configure Oracle GoldenGate as appropriate for your environment.

12.3.2 Adding as a Windows Cluster Resource

When installing Oracle GoldenGate in a Windows cluster, follow these instructions to establish Oracle GoldenGate as a cluster resource and configure the Manager service correctly on all nodes.

  • In the cluster administrator, add the Manager process to the group that contains the database instance to which Oracle GoldenGate will connect.

  • Make sure all nodes on which Oracle GoldenGate will run are selected as possible owners of the resource.

  • Make certain the Manager Windows service has the following dependencies (configurable from the Services control panel):

    • The database resource

    • The disk resource that contains the Oracle GoldenGate directory

    • The disk resource that contains the database transaction log files

    • The disk resource that contains the database transaction log backup files