Jim Nissen writes:
> No, asking simply because the Solaris tunables guide list both those TCP 
> settings that are changed via ndd and other that are /etc/system.  
> Customer's asking me if exclusive IP will allow for a NGZ to have its 
> own /etc/system TCP tunables, or if they are global.

/etc/system is still global because there's still only one system
kernel.  That's the essence of zones.

/etc/system and ndd are unrelated, which is what confused me here.
Except for a few cases where there are "mirrored" bits (and likely
things that are actually bugs), you can't set ndd variables in
/etc/system, and you can't set /etc/system variables via ndd, and this
is by design.

/etc/system works by scribbling on top of kernel storage named by
symbols in the object files.  It's essentially equivalent to "/W" in
mdb during the boot process -- you're writing directly to a variable,
and perhaps even one that's declared "static" by the original author.

ndd is more programmatic.  It opens the named device node (e.g,
/dev/tcp) and issues an undocumented ioctl.  The driver (and any
STREAMS modules in between) then gets the ioctl and can decide to do
anything it wants with it.  Sometimes, it sets a variable somewhere,
or perhaps modifies multiple variables.  Other ndd ioctls cause other
functions to be called, locks to be taken, and other work done.
Unlike /etc/system, the possibilities are endless.

James Carlson, Solaris Networking              <[EMAIL PROTECTED]>
Sun Microsystems / 35 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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