Boyd Adamson writes:
> James Carlson <[EMAIL PROTECTED]> writes:
> > Solaris systems don't have such a thing as a "Primary IP address."
> > There is such a concept as a "primary interface name," but it's
> > meaningful only with respect to the current DHCP client
> > implementation: the "primary interface" is the one for which
> > /sbin/dhcpinfo will return results if you don't specify a particular
> > interface with "-i".
> 
> Out of interest, what about the "primary" keyword in sysidcfg(4)? What
> exactly does it do?

There's a staggering amount of logic spread throughout the Install
consolidation for that, but it affects only the way installation
works.

The "primary" interface in sysidcfg is associated with the system name
(setting hostname in a networking_interface clause with the primary
flag causes the system node name to be set to that string).  The
Install logic also plumbs up and configures that interface first, so
if you're doing something frightening (such as looking up other
interface addresses or -- horrors! -- netmasks via name services),
your name servers are 'assumed' to be located via that interface.  But
only during install time.

There are other things done during install time here, such as choosing
locale, that appear to depend on the sysid "primary" interface, but
the usage seems murky to me.

The relationship between this use of the word "primary" and DHCP's use
seems tenuous at best.  My read of the code in sysidnet says that when
Install invokes DHCP on an interface, it _always_ marks the interface
with the ifconfig "primary" keyword.  Thus, if you were to have
multiple DHCP interfaces, they'd all be set that way.  (DHCP will
treat the last one set as the "primary" for purposes of dhcpinfo.)

As the sysidtool(1M) pages explain, the sysid logic runs just once --
after a system is first installed or after it's been "unconfigured"
and rebooted.  Once it's been run, it has nothing to do with ordinary
system operation.

I think there's an effort in the install community to replace sysid.
I hope it reduces some of this obscurity.

-- 
James Carlson, Solaris Networking              <[EMAIL PROTECTED]>
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
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