Windows 7 and SLAAC?

David Horn dhorn2000 at
Tue Mar 30 13:54:37 CEST 2010

On Tue, Mar 30, 2010 at 7:27 AM, Gert Doering <gert at> wrote:
> Hi,
> I did an IPv6 training for a customer today, and discovered something
> interesting - Windows 7 doesn't use the MAC address of an interface
> for EUI64-based stateless autoconfiguration, but "something else".
> The host part is the same for the fe80:: and the global IPv6 address,
> but it's something completely unrelated to the MAC address.
> Does one of you have a pointer for me what Windows 7 is using here?  Some
> sort of "windows installation global identifier"?

Microsoft has a "Cable Guy" article that describes Vista/Win 7
autoconf behavior, including the netsh CLI interface syntax for this
particular setting.

netsh interface ipv6 set global randomize­identifiers=disabled  for
more information.

Good Luck.

---_Dave Horn

> WinXP uses the MAC address, have no Vista to test right now...
> Gert Doering
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