HP OpenVMS Systems

Halts caused by serial console line access?

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The Question is:

 
I will be performing VMS upgrades to V6.2 on about
25 systems located at one of our remote sites.  I need to
be able to log all of the upgrade.  Set Host/log
won't be sufficient because several reboots occurr during the
upgrade.  What I need to be able to do is connect the console
port of the upgrade system to a serial port of a
near by system.  I will not have access to PCM, so it is
not a solution, although I know that with this software and
the right terminal server, I would be home free.  I have
been working with a MicroVAX 3100-80 and 3100-90
trying to use the 3100-80 TTA2 port as the console
for the 3100-90 system.  However this causes the
system to halt every time I do anything that touches
the TTA2 port on the 3100-80, such as $SHOW TERM TTA2:
or $SHOW DEVICE TTA2: or $SET HOST/DTE TTA2:  What is the
technique for implementing this configuration without
crashing the system?
 
 

The Answer is :

 
  It would appear you have the speed set incorrectly on the console serial
  port, and this is effectively a serial line framing error, which itself
  is effectively a BREAK signal, which effectively halts the system.  This
  assumes that the activities that halt the system involve anything that
  might cause input (and specifically framing errors) to be received on
  the console serial line.
 
  One available approach to achieving the logging is via SET HOST/LOG/DTE
  via a modem on the console serial line.  Beware that leaving this modem
  connected can potentially open a security hole, as access to the system
  console should be controlled.  A directly-connected serial line is also
  possible, either via another host port or via a DECserver.  (Some form
  of electrical isolation -- such as a fiber-optic coupler -- is generally
  prefered when connecting directly to the serial line.)
 

  

     

     
answer written or last revised on ( 2-AUG-1999 )
     
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