Re: Host ID.

On Mon, Apr 09, 2007 at 01:35:39PM -0400, Jung-uk Kim wrote:
On Sunday 08 April 2007 11:13 am, Pawel Jakub Dawidek wrote:
On Sun, Apr 08, 2007 at 10:04:16PM +0900, gnn@xxxxxxxxxxx wrote:
I noted that someone mentioned using a network based ID. Since
EUI-64 are unique I would suspect they would be the best source
for this on systems that don't naturally have a hostid concept.
See Appendix A of RFC 2373 for how to create an EUI-64 Interface
Identifier.

The only problem with this approach that I see is that if you
remove that interface (that is it was on a card not on your
motherboard) then it goes away. Perhaps generating this and
storing it, no matter what the future network configuration of
the system is, is the right way to go.

So why not generate it and be done with it? And what if you move
your card to another box were you're planning to install new
system?

Actually uuidgen(2) uses uuid(3) and uuid(3) generates UUID version 1
string, i.e., it is based on timestamp and MAC address already. :-)

But in my proposal we generate UUID only once and store it as it is,
which means are keep the same UUID even if network card has changed.

I'd really like to make it simple and consistent on all archs, so
one knows exactly what to expect.

Agreed. But I also agree with imp, i.e., we have to utilize hardware
UUID if it is available and valid for the platform.

I don't agree. As Robert pointed out there are situation you would like
to share the same UUID between many hosts.

I'm committing as it is, we may change it in the future.

--
Pawel Jakub Dawidek http://www.wheel.pl
pjd@xxxxxxxxxxx http://www.FreeBSD.org
FreeBSD committer Am I Evil? Yes, I Am!

Attachment: pgpxMaBFviByq.pgp
Description: PGP signature

Relevant Pages

  • Re: Host ID.
    ... See Appendix A of RFC 2373 for how to create an EUI-64 Interface ... your card to another box were you're planning to install new ... But in my proposal we generate UUID only once and store it as it is, ... But I also agree with imp, i.e., we have to utilize hardware ...
    (freebsd-arch)
  • Re: Host ID.
    ... See Appendix A of RFC 2373 for how to create an EUI-64 Interface ... your card to another box were you're planning to install new ... Unfortunately some SMBIOS contain broken UUIDs, e.g., they don't ... If it does not conform RFC4122, ...
    (freebsd-arch)