Host ID.

[Andrew Pantyukhin]

On 4/7/07, Pawel Jakub Dawidek <pjd at freebsd.org> wrote:
> On Sat, Apr 07, 2007 at 05:07:25PM +0400, Andrew Pantyukhin wrote:
> > - Is Windows-style hardware ID's hashing totally ruled out?
>
> I know nothing about it...

Well, maybe something like hashing MAC of the first NIC
to get the initial ID... But then there's always the
probability that we initialize several systems putting
the same NIC into each of them...

> > - How does it work in other OS'es? (e.g. solaris /bin/hostid)
>
> On OpenSolaris, if I understand the code right, hostid is derived from
> hw_serial, and hw_serial is taken from:
>
>  * On sparc machines, read hw_serial from the firmware at boot time
>  * and simply assert Sun is the hardware provider.  Hmm.
> [...]
>  * On x86 machines, read hw_serial, hw_provider and srpc_domain from
>  * /etc/bootrc at boot time.

There's even a business [1] selling software to change
Solaris hostid for £49. Should I squat freebsdhostid.com? :)

[1] http://www.solarishostid.com/

Anyway, other systems also have a notion of hostid. It
appears from this linux manpage that hostid was there
in 4.2BSD, but got removed in 4.4BSD:

http://www.die.net/doc/linux/man/man2/gethostid.2.html