[aperi-dev] SMI-S Host Profile Support Investigation

[Khan M Tasinga <kmtasing@xxxxxxxxxx>]

Aperi gathers information about the
Host Bus Adapters (HBAs) and Fibre Channel (FC) ports on a given host system
through the Fabric Agent. SMI-S defines a set of Host Profiles which provide
an alternative, standard, means by which to collect the same information.
Adding support for SMI-S Host Profiles to Aperi would make it possible
to obtain HBA and FC port information from a host system without installing
the Fabric Agent. Implemented in conjunction with support for the SMI-S
Fabric Topology Profiles, it might be possible to deprecate the entire
Fabric Agent and begin moving Aperi in the direction of agentless storage
management. What follows are some notes related to support for SMI-S Host
Profiles in Aperi. An investigation of what it would take to add such functionality
to Aperi is ongoing. Feedback is more than welcome.

SMI-S 1.1 defines the following five
Host Profiles:

- FC HBA Profile
- iSCSI Initiator Profile (EXPERIMENTAL)
- Host Discovered Resources (EXPERIMENTAL)
- Disk Partition Subprofile (EXPERIMENTAL)
- SCSI Multipath Management Subprofile
(EXPERIMENTAL)

Of the five Host Profiles listed above,
replicating the functionality provided by the Fabric Agent requires the
support the FC HBA Profile, and possibly the Host Discovered Resources
(HDR) Profile. (Further investigation is required.) There are at least
two HBA vendors which distribute SMI-S CTP certified providers for the
FC HBA Profile. Emulex offers its SMI-S Provider Kit on Windows. QLogic
offers its HBA CIM Provider on both Windows and Linux. Additionally, in
the QLogic HBA CIM Provider, support for the HDR Profile, though not SMI-S
CTP certified, can be enabled by setting a flag in a configuration file.
More providers with support for the SMI-S Host Profiles may become available
throughout 2007. However, should Aperi choose to go forward with the implementing
support for SMI-S Host Profiles, the providers offered by Emulex and QLogic
should be adequate for development and test.

Here is a preliminary, high-level, outline
of the work that would be required to add support for SMI-S Host Profiles
to Aperi:

* Database schema. Given that Aperi
already collects information available in the SMI-S Host Profiles, the
database schema might not require many additions and / or modifications.
Further investigation is necessary.
* CIMOM discovery. The discovery engine
would need to be updated to recognize CIMOMs with support for SMI-S Host
Profiles.
* CIMOM probe. A new probe job would
have to be written to collect information from CIMOMs with support for
SMI-S Host Profiles.
        -
Database mappers. New mappers would need to be written to take the information
provided by CIMOMs and store it in the Aperi database.
        -
Monitoring / change detection. With HBA and FC port support already available,
the appropriate infrastructure might already be in place for detecting
changes in the environment. However, further        
investigation is necessary.
* GUI. Work in this area would be, to
some extent, tied to whatever work is done with the schema. Given that
Aperi already presents HBA and FC port information, a lot of what is needed
is likely already in place. However, if new information is available in
the SMI-S Host Profiles, relative to what is already collected, the GUI
would have to be updated to present that new information to the user (topology
viewer, reports, etc.). Further investigation is necessary. At a minimum,
some GUI work would be required to support the CIMOM discovery and CIMOM
probe stuff mentioned above (e.g., adding a node to the navigation tree
for a new probe job).

Most of the work associated with adding
support for SMI-S Host Profiles to Aperi would be in the Device Server.
The Device Server provides tree key abstract functions: discovery, monitoring,
and control. Of those three, the focus would be largely confined to discovery.
I’m not yet too familiar with the internal workings of the Device Server.
However, from what I know and the discussions I’ve had with various folks,
if I had to give a preliminary sizing, my sense is that the addition of
support for SMI-S Host Profiles to Aperi is a 4 to 6 PM effort.

Thoughts? Again, feedback is welcome.

Regards,
Khan Tasinga
IBM Tivoli Software Engineer / Aperi Development
Phone: (408) 284-5142 | T/L: 8-953-5142
Email: kmtasing@xxxxxxxxxx