On Fri, 25 Jun 1999, Eduardo E. Horvath wrote:

>We've been hashing this issue out quite a bit.  Since a Fibre Channel card
>is by definition a fibre channel controller, each card should have a
>unique WWN that is used for the node WWN.  If you swap a controller, the
>node WWN should change.

I've just had a quick look at a Sun Ultra 3500.  This has an SBus FC-AL
card with two GBICs, each GBIC being connnected to a SENA.  There's also
another FC-AL built into the I/O module which attaches the internal disk
backplane.

Poking about with luxadm, I found that the SBus FC-AL has TWO WWNs (one
for each channel), and each SENA also has a WWN.  On one channel, the
WWNs of the SBus card and the SENA are consecutive, but the two WWNs
belonging to the SBus card aren't.  As two of the GBICs were supplied
separately, this sort of suggests that the WWN might live in the GBIC
(rather than the SBus card or the SENA backplane).

I couldn't get luxadm to show the WWNs for the FC-AL controller which
connects the internal disk backplane, but presumably this has another
two, so for this machine you might have 4 WWNs to choose from!


Roger

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Roger Brooks (Systems Programmer),          |  Email: R.S.Brooks@liv.ac.uk
Computing Services Dept,                    |  Tel:   +44 151 794 4441
The University of Liverpool,                |  Fax:   +44 151 794 4442
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