Excuse this probable waste of bandwidth but I know we have some very
devoted Macintosh gurus out there.  Let me crosspost an item that I
sent to comp.dcom.sys.cisco...

I am working on replacing some old shared media Synoptics [Bay] 2803
hubs <cough, choke> with Catalyst 2924s.  I have migrated over 100
ports to date without incident -- until today.

There is one drop that is well within specs (Category 5, 35 meters) with
an older Macintosh (Mac-II I think) on the other end.  You can plug it
into any of the Synoptics ports and immediately get a link.  But plug
it into any of the Catalyst ports and nothing - zilch, nada, nothing.
No flicker of the port status LED, no message on the console, zero.

Since the work today was on a "live" network I couldn't do any further
checks of the Mac as to interface card, etc., but I thought it weird
that only this *one* station works fine on *any* Synoptics port but
will not establish a link on *any* Catalyst port, with or without
spanning tree enabled (implicitly turning off/on the portfast toggle,
but before you ask, no, there are no redundant links, this is just a
straightforward star topology from the MDF to the floor).

Jeff Kell <[log in to unmask]>
Systems Administrator/Network Engineer
University of Tennessee at Chattanooga