Sunay Tripathi writes:
> James Carlson wrote:
> > What are the administrators actually doing with these MAC addresses
> > that causes them to prefer failure?
> >
>
> Factory assigned MAC addresses are inventoried entities in some
> companies. They keep track of the MAC address(s) the machine has along
> with other information (like physical location etc). Sparc's have a
> hostid but on x86, this is the only unique way to identify the physical
> machines from the packet on the network.
Sure. And you can tell which address you've got (if you care) by
using the status command.
And I'd point out that after any move, you would *need* to look at the
address on the interface, because the new physical interface likely
has a different set of MAC addresses on it, and you're going to need
to update those crufty tables (such as /etc/ethers).
I'd even see no problem with issuing a warning when the
use-random-fallback event occurs:
Warning: you asked for a factory address, but I couldn't get
one. I've assigned a random address instead. If that's not
ok, then you'll probably want to reconfigure this interface.
(Or perhaps something more professional-looking than that.)
The problem I have is with the failure mode. I don't see a purpose.
> Random MAC addresses are random at best and have no guarantees that
> they are unique across different machines. The virtualization crowd
> has adopted random mac address but a sizable set of customers are
> still skeptical about duplication etc.
I understand why users would want to prefer factory addresses. I
wasn't questioning that at all.
I don't understand why they would prefer to see failure. It doesn't
seem helpful.
Would users actually be inconvenienced if an interface worked because
it fell back to a random address, where they'd actually have an
advantage if it failed instead?
--
James Carlson, Solaris Networking <james.d.carlson at sun.com>
Sun Microsystems / 1 Network Drive 71.232W Vox +1 781 442 2084
MS UBUR02-212 / Burlington MA 01803-2757 42.496N Fax +1 781 442 1677
