To make an application highly available, the application must be managed as a resource in an application resource group.
All of the entities that you configure for the application resource group on the primary cluster, such as application data resources, configuration files, and resource groups, must be replicated to the secondary cluster. The resource group names must be identical on both clusters. Also, the data that the application resource uses must be replicated to the secondary cluster.
This section contains information about the following tasks:
You can add an existing resource group to the list of application resource groups for a protection group. Before you add an application resource group to a protection group, ensure that the following conditions are met:
The protection group is defined.
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 view this property by using the clresourcegroup show command.
# clresourcegroup show -p auto_start_on_new_cluster apprg |
Set the Auto_start_on_new_cluster property to False as follows:
# 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. Therefore, after the Sun Cluster Geographic Edition software restarts and communicates with the remote cluster to ensure that the remote cluster is running and that the remote cluster is the secondary cluster for that resource group. The Sun Cluster Geographic Edition software does not automatically start the resource group on the primary cluster.
Application resource groups should be online only on primary cluster when the protection group is activated.
The Nodelist property of the failover application resource group that has affinities with a device group defined by the resource must contain the same entries in identical order to the Nodelist property of the protection group.
The application resource group must not have dependencies on resource groups and resources outside of this protection group. To add several application resource groups that share dependencies, you must 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 will fail.
The protection group can be activated or deactivated and the resource group can be either Online or Unmanaged.
If the resource group is Unamanged and the protection group is activated after the configuration of the protection group has changed, then 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. You must activate the protection group before adding an online resource group.
Log in to a cluster node.
You must be assigned the Geo Management RBAC rights profile to complete this procedure. 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.
# 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. Then the command propagates the new configuration information to the partner cluster if the partner cluster contains a protection group of the same name.
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 status is set to OK on the local cluster.
If the Configuration status is OK on the local cluster, but the add operation is unsuccessful on the partner cluster, 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.
If the application resource group is a failover type resource group that shares affinities with a device group in the same protection group, the Sun Cluster Geographic Edition software alters its RG_affinities property to include a strong, positive affinity to an internal resource group, called a lightweight resource group. This affinity includes failover delegation.
The application resource group must not have strong, positive affinities that have failover delegation with other resource groups. Otherwise, trying to include a strong positive affinity with failover delegation on the lightweight resource group fails.
The Sun Cluster Geographic Edition software also creates strong dependencies between the HAStoragePlus resource in the application resource group and the HAStoragePlus resource in the lightweight resource group for this device group. This redirection occurs when the protection group is brought online or when an online application resource group is added to an online protection group.
Do not modify dependencies and resource group affinities between application resource groups and lightweight resource groups.
This example adds two application resource groups, apprg1 and apprg2, to avspg.
# geopg add-resource-group apprg1,apprg2 avspg |
You can remove an application resource group from a protection group without altering the state or contents of the application resource group.
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.
You must be assigned the Geo Management RBAC rights profile to complete this procedure. 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.
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.
# 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.
If the resource group that is being removed shares dependencies with other resource groups in the protection group, then you must also remove all other resource groups that share dependencies with the resource group that is being removed.
If the remove operation failed on the local cluster, the configuration of the protection group is not modified. Otherwise, the Configuration status is set to OK on the local cluster.
If the Configuration status is OK on the local cluster, but the remove operation is unsuccessful on the partner cluster, the Configuration status is set to Error on the partner cluster.
Sun Cluster Geographic Edition software removes the affinity and resource dependencies between the application resource group and the lightweight resource group.
This example removes two application resource groups, apprg1 and apprg2, from avspg.
# geopg remove-resource-group apprg1,apprg2 avspg |