HP OpenVMS Systems

Enabling Telnet keepalive?

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The Question is:

 
TELNET devices TN* and DECserver 90
 
My application is gathering messages over serial lines connected to the
 DECserver ports and its behaviour is optimal using LAT devices.
 
Now I am forced to change to TCP/IP.
 
As in various wizard discussions recommended I defined on DECserver:
change telnet listener 2001 port 1
change telnet listener 2001 connections enable
and in VMS:
telnet <address>/create_session 2001 2001
 
And my application runs well with unchanged qio-read.
 
BUT: on network or power failure nothing happens to the TNA2001! Thus the
 application is not able to recognize a failure and to reconnect.
 
Is there a solution thru more detailed DECserver or TELNET configuration? Or is
 this way too simple so that I must try other techniques, e.g. direct socket
 programming ( where do I find examples )?
 
Kind regards
Robert Kohl
 
p.s.:
ucx sh vers
 
Digital TCP/IP Services for OpenVMS Alpha Version V4.1 - ECO 8
on a AlphaStation 255/300 running OpenVMS V7.1
 

The Answer is :

 
  Poll the device (via ping or in-band character transfer) at periodic
  intervals?
 
  Consider the UCX$TELNET_KEEPALIVE logical name, or its equivilent in
  V5 and later: SET SERVICE FTP/SOCKET_OPTIONS=KEEPALIVE mechanism?
 
  Consider an upgrade to TCP/IP Services V5.0A, as V4.1 is very old.
 

  

     

     
answer written or last revised on ( 11-JUL-2000 )
     
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