P1394 Mail Archive: Re: P1394> Dynamic LUNs

P1394 Mail Archive: Re: P1394> Dynamic LUNs

Re: P1394> Dynamic LUNs

Greg Shue (gregs@sdd.hp.com)
Thu, 14 May 1998 17:03:08 -0700 (PDT)

Here's some comments on the Dynamic LUN notes sent out by Alan.

A) I don't think the Dynamic Logical Unit Number scheme was
intended to _multiplex_ applications to device functions.
I think it is intended on providing the ability for a node
to establish a unique connection to identical instances of
a service without having to:

1- Assign fixed LUNs for each service instance
2- Crowd the Config ROM with redundant information

B) After discussions with folks from Microsoft, I would strongly
recommend NOT using LUN 0 (zero) for anything but a direct
connection to an instance of the transport client. The LUN-server
could easily be identified in the Config ROM as belonging to
a different LUN. (Since it's really a different service
than the transport client.)

C) The SBP-2 initiator and target drivers do not change a bit.
Reconnect proceeds normally. The initiator and target SBP-2
drivers must already remember LUNs, EUI-64 values, and LoginIDs.

D) The SBP-2 driver probably will already map connections (LoginIDs?)
to a socket ID or some other appropriate OS mechanism.

It still strikes me as a clean, simple way to get beyond the constraints
of SBP-2 when appropriate. Best of all, it's optional!

Greg Shue
Hewlett-Packard Company
Office Products Division			gregs@sdd.hp.com