When I first worked in the US I worked with Brian Redman who
held a patent on the box used widely within Bell Labs which allowed
simultaneous access to a computer's serial console from both the
physical console and another serial line, usually connected to
either a modem or a Datakit node (Redman et al, 4479122, Remote
controlled switched access to the console port of an electronic
computer). We still have many of these boxes. However, there was
a variant box which had another serial input port which activated
a relay between two extra output lines when CTS (?) was asserted.
These lines could be attached to the reset pins on a conmputer
to cause it to to the right thing. At some point in the 90s most
of these were thrown out when I wasn't looking. I have one left
and it lets me reboot my test system remotely by simply
C office2</dev/null
where office2 is a serial port on a console server to which the
reboot box is attached.
Three or four years ago I started work on a replacement with a
hardware guy here, it was going to use the parallel port and a
CAT5 patch panel to access to a bunch of computers. Unfortunately
my colleague took the eary retirement package before we got it
past the planning stages.
I'm sure there's someone out there with enough hardware smarts to
produce a replacement, it really is a great thing to have and it's
a lot less strain on the system than a remote power switch (we
have an APC one and it requires wading through menus in both serial
and web access modes).
--jim
