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Re: how do I disable IPv6?

    Date:        Tue, 27 Feb 2018 22:25:20 -0800
    From:        John Nemeth <>
    Message-ID:  <>

  |      Is Sun an unscrupulous vendor?  Traditionally, all network
  | interfaces on a Sun box had the same MAC address.

One could argue that they are the one vendor doing things correctly
(that is, as originally intended.)    Of course, in the early days, with
true shared media ethernet, connecting more than one interface to
a single LAN (other than for reduncancy, where having the same
MAC addr is an advantage) was pointless.

The world didn't end up going that way, largely because on (almost)
all other vendors' systems ethernet was an add on, and not a basic
part of the system - the MAC addr had to be delivered with the add
in board, or you wouldn't have one - and so if you were rich enough to
buy two for one system, you ended up with 2 MAC addrs.

And then switches made it sometimes be rational to connect multiple
times to the same LAN.

That isn't the type of thing that was of concern - rather the kind of
vendor who is too cheap to set up a reliable process (or so it is
rumored, any process) for assigning unique MAC addresses at
all - the "accidental duplication" that Gert Doering mentioned in
his message could happen to anyone, and in the overall scheme of
things is really unlikely (not impossible obviously) to actually result
in a duplicate on the same LAN.

The mythical (maybe) unscrupulous vendor is one that was supposed
to assign the same MAC addr to everything shipped (or perhaps a
small range of MAC addrs).   Whether there ever was such a vendor
I have no idea.


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