Online Reconfiguration of Generic Resources

Online operations such as addition, deletion, and modification of generic resources in packages are supported. The operations that can be performed online are:

Addition of a generic resource of generic_resource_evaluation_type set to during_package_start, if the status of the generic resource is not 'down'.

Please ensure that while adding a generic resource, the equivalent monitor is available; if not add the monitor while adding a generic resource.

Addition of a generic resource of generic_resource_evaluation_type set to before_package_start, whose status is 'up'.

Deletion of a generic resource. Please ensure that while deleting a generic resource, the equivalent monitor is also removed. However, if a common resource is being monitored across multiple packages, then before removing the monitor ensure that the generic resource being deleted is not configured in other packages that are also using this monitor.

Modification of generic_resource_evaluation_type from before_package_start to during_package_start or vice versa when the resource is 'up'.

Modification of generic_resource_up_criteria specified for resources of evaluation type before_package_start or during_package_start provided the new up criteria does not cause the resource status to evaluate to 'down' (i.e., the current_value of the resource still satisfies the new up_criteria).

Modification of resource type from a simple resource to an extended resource is allowed only if the generic_resource_evaluation_type is during_package_start in all the running packages that currently use the resource.

Parameters for Configuring EMS Resources

NOTE: The default form for parameter names and literal values in the modular package configuration file is lower case; for legacy packages the default is upper case. There are no compatibility issues; Serviceguard is case-insensitive as far as the parameters are concerned. This manual uses lower case, unless the parameter in question is used only in legacy packages, or the context refers exclusively to such a package.

Serviceguard provides a set of parameters for configuring EMS (Event Monitoring Service) resources. These are resource_name, resource_polling_interval, resource_start, and resource_up_value. Configure each of these parameters in the package configuration file for each resource the package will be dependent on.

The resource_start parameter determines when Serviceguard starts up resource monitoring for EMS resources. resource_start can be set to either automatic or deferred.

Serviceguard will start up resource monitoring for automatic resources automatically when the Serviceguard cluster daemon starts up on the node.

Serviceguard will not attempt to start deferred resource monitoring during node startup, but will start monitoring these resources when the package runs.

The following is an example of how to configure deferred and automatic resources.

resource_name /net/interfaces/lan/status/lan0 resource_polling_interval 60 resource_start deferred resource_up_value = up

resource_name /net/interfaces/lan/status/lan1 resource_polling_interval 60 resource_start deferred resource_up_value = up

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HP Serviceguard manual Parameters for Configuring EMS Resources, Online Reconfiguration of Generic Resources