To make an application highly available, you must ensure that the application is managed as a resource in an application resource group. Unlike other data replication modules, the Oracle RAC server proxy resource group is not added to the protection group. Instead, a shadow RAC server proxy resource group is added to represent this resource group.
You can add and remove the Oracle shadow RAC server proxy resource group to and from the protection group at any time without affecting the Oracle Data Guard data replication. This fact does not prevent you from adding other, non-RAC server proxy resource groups to the protection group if necessary. However, these applications cannot use any data that requires replication to the standby cluster as only Oracle Data Guard is supported in this type of protection group.
You need to replicate, on the standby cluster, all entities that you configure for the primary cluster's application resource group. Examples of entities that you need to replicate are application data resources, configuration files, and resource groups. Resource group names must also match on both clusters. In addition, the data that the application resource uses needs to be replicated on the standby cluster.
This section shows you how to perform the following procedures:
How to Add an Application Resource Group to an Oracle Data Guard Protection Group
How to Delete an Application Resource Group From an Oracle Data Guard Protection Group
You can add an existing resource group, other than an Oracle RAC server proxy resource group containing an Oracle RAC server proxy resource, to the list of application resource groups for a protection group. If you do try to add an Oracle RAC server proxy resource group, the geopg command returns an error.
Before you add an application resource group (of any other type) to a protection group, ensure that the following conditions are met:
The protection group is defined.
The application resource group does not need any data replicating. You are not prevented from adding such resource groups, but the Oracle Data Guard module does not coordinate the switchover of other types of data replication.
The resource group to add already exists on both clusters and is in an appropriate state.
The Auto_start_on_new_cluster property of the resource group is set to False. You can determine the setting of this property by using the clresourcegroup show command.
phys-node-n# clresourcegroup show -p auto_start_on_new_cluster apprg |
Set the Auto_start_on_new_cluster property to False as follows:
phys-node-n# clresourcegroup set -p Auto_start_on_new_cluster=False apprg1 |
Setting the Auto_start_on_new_cluster property to False prevents the Sun Cluster resource group manager from automatically starting the resource groups in the protection group.
When the protection group is activated, application resource groups need to be online only on the primary cluster.
The application resource group does not have dependencies on resource groups and resources outside of this protection group unless the External_Dependency_Allowed protection group property is set to TRUE. To add several application resource groups that share dependencies while the External_Dependency_Allowed protection group property is set to FALSE, you need to add all the application resource groups that share dependencies to the protection group in a single operation. If you add the application resource groups separately, the operation fails.
The protection group can be activated or deactivated, and the resource group can be either Online or Unmanaged.
If the resource group is Unmanaged and the protection group is activated after the configuration of the protection group has changed, the local state of the protection group becomes Error.
If the resource group to add is Online and the protection group is deactivated, the request is rejected. Before you add an online resource group, you need to activate the protection group.
Log in to a cluster node.
To complete this step, you need to be assigned the Geo Management RBAC rights profile. For more information about RBAC, see Sun Cluster Geographic Edition Software and RBAC in Sun Cluster Geographic Edition System Administration Guide.
Add an application resource group to the protection group.
phys-node-n# geopg add-resource-group resourcegrouplist protectiongroup |
Specifies the name of the application resource group. You can specify more than one resource group in a comma-separated list.
Specifies the name of the protection group.
This command adds an application resource group to a protection group on the local cluster. If the partner cluster contains a protection group of the same name, the command then propagates the new configuration information to the partner cluster.
For information about the names and values that are supported by Sun Cluster Geographic Edition software, see Appendix B, Legal Names and Values of Sun Cluster Geographic Edition Entities, in Sun Cluster Geographic Edition System Administration Guide.
If the add operation is unsuccessful on the local cluster, the configuration of the protection group is not modified. Otherwise, the Configuration is added and its status is set to OK on the local cluster.
If the Configuration status is set to OK on the local cluster, but the add operation is unsuccessful on the partner cluster, the Configuration is added on the partner cluster and the configuration status is set to Error on the partner cluster.
After the application resource group is added to the protection group, the application resource group is managed as an entity of the protection group. Then, the application resource group is affected by protection group operations such as start, stop, switchover, and takeover.
This example shows how to add two application resource groups, apprg1 and apprg2, to sales-pg.
phys-paris-1# geopg add-resource-group apprg1,apprg2 sales-pg |
You can remove an application resource group from a protection group without altering the state or contents of the application resource group. You can remove Oracle shadow RAC server proxy resource groups at any time, without affecting the Oracle RAC server proxy resource groups or Oracle RAC databases that they represent. You can remove these resource groups because the shadow RAC server proxy resource groups simply reflect the status of the real Oracle RAC server proxy resource groups and do not control the Oracle RAC databases.
Ensure that the following conditions are met:
The protection group is defined on the local cluster.
The resource group to remove is part of the application resource groups of the protection group. For example, you cannot remove a resource group that belongs to the data replication management entity.
Log in to a cluster node.
To complete this step, you need to be assigned the Geo Management RBAC rights profile. For more information about RBAC, seeSun Cluster Geographic Edition Software and RBAC in Sun Cluster Geographic Edition System Administration Guide.
Remove the application resource group from the protection group.
phys-node-n# geopg remove-resource-group resourcegrouplist protectiongroup |
Specifies the name of the application resource group.
You can specify more than one resource group in a comma-separated list.
Specifies the name of the protection group.
This command removes an application resource group from a protection group on the local cluster. If the partner cluster contains a protection group of the same name, the application resource group is also removed from the protection group of the partner cluster.
If the resource group that is being removed shares dependencies with other resource groups in the protection group and the External_Dependency_Allowed protection group property is set to FALSE, you also need to remove all other resource groups that share dependencies with the resource group that is being removed.
If the remove operation fails on the local cluster, the configuration of the protection group is not modified. Otherwise, the Configuration is removed and its status is set to OK on the local cluster.
If the Configuration status is set to OK on the local cluster, but the remove operation is unsuccessful on the partner cluster, the Configuration is removed from the partner cluster and the configuration status is set to Error on the partner cluster.
This example shows how to remove two application resource groups, apprg1 and apprg2, from sales-pg.
phys-paris-1# geopg remove-resource-group apprg1,apprg2 sales-pg |