Upcoming SA Forum Specification Release Addresses Hardware/Software Interaction
By Ulrich Kleber, Service Availability Forum

Release 6 of the SA Forum specifications will address the interaction between hardware events and software entities for true service availability. This is a critical area to drive commonality and broaden the specifications, just as Release 5 prepared the way for Java integration and was followed by Java mapping services in June 2008.

The upcoming release introduces a new service called the Platform Management Service (PLM). It bridges between the Hardware Platform Interface (HPI) and the Application Interface Specification (AIS). Release 6 will also contain major enhancements to HPI and the SA Forum’s Information Model Management Service (IMM). These enhancements improve the services enabled by previous releases, while preserving backwards compatibility. That is, they allow implementations to support several interface versions in parallel, enabling a smooth migration to newer versions.

The new PLM Service introduces an information model which represents the hardware entities discovered by HPI for applications and middleware services. This logical representation not only creates a new abstraction layer appropriate for software usage, but also allows developers to match the configured system to hardware that is actually present, and makes relevant hardware states easily accessible from software via a convenient state model. Similarly, PLM extends the information model with managed objects that represent operating systems and virtualization layers. Administrative commands can be used for platform maintenance. The complete information model will allow fault correlation over all platform layers up to the application. This function nicely supports management of AdvancedTCA systems with their sophisticated out-of-band management and hot swap capabilities.

The introduction of the PLM service is accompanied by enhancements of the Cluster Management Service (CLM) and the Availability Management Framework (AMF), using PLM’s inherent fault correlation support.

The second major enhancement of Release 6 is the extension of IMM by structuring object implementer interfaces to different roles. Processes can now register to validate configuration changes or to listen to changes, even if they are not an object’s runtime owner. This allows for reactions by processes doing global validation of changes, as well as by multiple processes.

In the HPI area, the interfaces for firmware upgrades are significantly improved, and several issues related to hot swap management are clarified. For instance, simplified hot swap is replaced by unmanaged hot swap for hardware entities whose hot swap state cannot be influenced by software. Other enhancements allow libraries to create threads controlled by the user, and allow dynamic updating of resources in a running system.

The SA Forum will describe the features of Release 6, including the new PLM service, at the AdvancedTCA Summit in Santa Clara in October (www.advancedtcasummit.com).