HBA APIs (Host Bus Adapter Application Programming Interface)

The Common HBA API is a standard "C" language Application Programming Interface for management of Fibre Channel Host Bus Adapters and discovery of SAN resources. As such, it defines a scope within which application software can be written without attention to vendor-specific infrastructure behavior. Included within the scope of the Common HBA API are vendor independent interfaces and services such as:

1. Observation and modification of descriptive and operational characteristics of Fibre Channel HBAs and ports;
2. Access to Fibre Channel Fabric Services;
3. Discovery and characterization of FCP-2 storage resources;
4. Access to Fibre Channel Extended Link Services sufficient to satisfy the FC-MI manageability profile for Host Bus Adapters;
5. Observation of Fibre Channel HBA, Port, and storage access traffic statistics;
6. Observation and modification of the availability and representation of Fibre Channel storage resources to Operating System applications;
7. Timely and selective reporting of HBA and fabric configuration, status, and statistical events.

The Common HBA API specification was developed in two phases. Phase 2, completed in March 2002, includes all of the feature groups listed above. Phase 1 was an early implementers version completed in September of 2000. It included feature groups 1-3 and partial support for the remaining feature groups.

An implementation of the Common HBA API specification of either phase is based on two classes of software: A set of Vendor Specific Libraries each of which provides the standard API functions for a vendor specific HBA driver, and a Common Library which provides a single entry point for each standard API function even when HBAs from multiple vendors are present.

Specifications

The specifications for both phases of the Common HBA API have been released to ANSI T11 for publication.

• The specification for Common HBA API Phase 1 is Annex A to T11 FC-MI
• The specification for Common HBA API Phase 2 is T11 Document 02-149v0

Implementations

Implementations of the Common HBA API are provided by vendors of Fibre Channel HBAs and subsystems and SAN Management Software. SNIA also sponsors an open-development reference implementation of the Common Library for both phases at SourceForge Forum hbaapi.

The source code for a reference implementation of the Common Library supporting both phases of the Common HBA API is maintained in the SourceForge HBA API Project. Source for a reference implementation of an older Common Library supporting only Phase 1 can also be found there.

Support

Questions concerning the specification and possible new feature should be submitted to the SNIA FC reflector snia-snmwg-fc@snia.org.

Key Programs