> "Brian Hechinger" <wonko@4amlunch.net> wrote:

> On Sat, May 04, 2002 at 10:33:49PM -0700, Don Yuniskis wrote:
> >
> > > For what it's worth, I have a DEC vt510 terminal, and can plug and
unplug
> > > at will from both of my Sun SS5 machines.  I'm fairly certain the
vt310
> >
> > Have you tried various "conditions" (powered, off, etc.)?  Or, do
> > you tend to always connect/disconnect following the same "routine"?
>
> under solaris, i noticed that if i unplugged my laptop from the serial
console
> of a variety of ultrasparc machines (from the lowly single cpu clone, to
the
> beastly UE6500) and was current logged in, they wouldn't break, but when i
> pulled the cable sitting at a login: prompt, they would break to rom.  the

Hmmm... this seems to confirm that the ROM/UART driver/whatever
doesn't unilaterally decide to invoke the monitor.  I.e. that there are
places where extra smarts could be added to condition the detected
"BREAK" and act accordingly.

Interesting choice of behaviors -- one could argue that while logged
in you would be most likely to want to invoke the monitor (because
you just *did* something that went FUBAR).

Also appears the use of BREAK to select among a variety of
port configurations (gettytab(5)?) is not supported?

> solution?  just stay logged in when disconnecting the serial console. ;)

Ah, so we now have yet another criteria to use the serial port... :>
sequence power at the right time, login before disconnecting, etc.  ;-)

I guess you should also login *before* connecting the cable if
you really want to ensure the BREAK doesn't occur there???

> i'll have to fart around with my older sparc hardware that i have at home.
> unfortunately, most of it is production, so it's not a good idea to just
> fool around with. ;)

Gee, you mean they frown on a server suddenly and abruptly dropping
into the monitor just because someone plugged/unplugged/powered/unpowered
a serial console?  (sigh)  Some folks just have *no* sense of humor...  :>
They'd probably get annoyed when you pull the fire alarm, too!  :>