Kevin,
This has been reworded a bit from the old ADC,
apparently to include task management requests. Perhaps the wording
needs to be cleaned up a bit. What would the normal response be for a LUN
that reports 001b for its peripheral qualifier in the Inquiry
data?
Some mention of the "DT device primary port(s)" needs to be
maintained, since you still need the LUNs responsive to the ADT port when the
LUNs are disabled . Failure to respond on the ADT port could be extremely
frustrating to recover from, especially if the mode page was saved with
ENABLE=0.
-roger
Clause 6.2.2.3.3 of ADC-2r8 has the
following sentence.
An ENABLE bit set to
zero specifies that the DT device primary port(s) associated with the SMC
logical unit shall not respond to commands and task management requests received
on the DT device primary port(s)
Clause 6.2.2.3.3 SMC logical unit descriptor format is describing Logical
units and how they are configured. It seems to me that the enable bit
should be related to how the SMC logical unit behaves and not how a port
behaves. In my thinking the enable bit should be enabling the logical unit
or disabling it. The correct response to a command directed at it should
be to return a 5/2500 ILLEGAL REQUEST LOGICAL UNIT NOT SUPPORTED. As ADC-2
reads it says the port shall not respond to any commands or task management
functions received on the device primary port(s). So I cannot respond to
anything directed at LUN 0 either.
If you make a stretch and say that "the DT device primary port(s)
associated with the SMC logical unit" means that it only applies to the port
when the LUN field specifies the SMC logical unit, then we have the behavior
that the device drops all requests that are either commands or task management
requests and makes no response to the host. This seems weird to have a
port respond to transport specific communications (e.g., selection, LIP, etc)
and to requests targeted at other LUNs but to go silent and not respond to those
directed at a specific LUN. I think the HBA will think the device has
disappeared or has hung.
This is the
same wording for the other LUN pages also.
Am I missing something?
Thanks,
Kevin D. Butt
SCSI
& Fibre Channel Architect, Tape Firmware
MS 6TYA, 9000 S. Rita Rd.,
Tucson, AZ 85744
Tel: 520-799-2869 / 520-799-5280
Fax: 520-799-2723
(T/L:321)
Email address:
kdbutt@us.ibm.com
http://www-03.ibm.com/servers/storage/