From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: generating a Linux WWN?
Date: Sat, 06 Oct 2007 19:46:25 -0700 (PDT)
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From: James Bottomley <James.Bottomley@SteelEye.com>
Date: Sat, 06 Oct 2007 09:11:10 -0500

> My problem with auto generated is that it's provably impossible to
> generate globally unique numbers for WWNs without some internal source
> of uniqueness (I know sparcs have this in their serial number, but most
> PCs unfortunately don't).

If you have at least one ethernet NIC, you have at least one
globally unique MAC address, which is 6 bytes of uniqueness to
draw from.

I'm sure there are countless other possibilities.

I think the SAN issue is way overstated.  Sure it's real, but
so are SHA conflicts in the kernel GIT repository.