[Info-vax] terminal servers etc

[Jan-Erik Soderholm]

Peter 'EPLAN' LANGSTOeGER wrote 2013-01-06 16:31:
> In article <kcakc6$4lr$1 at news.albasani.net>, Jan-Erik Soderholm <jan-erik.soderholm at telia.com> writes:
>> We are also moving all LAT into Telnet sessions. Note, these
>> are not for terminals, it's VMS that inits the connection to
>> the ports and detached apps connects the the LTA/TNA devices.
>
> Remember there is a slightly different implentation of Reverse-LAT
> and Reverse-TELNET (which I want to have changed for decades now ;-)
> and this also slightly differently in TCPIP and TCPware (sigh)...
>
> *) Reverse-TELNET requires the destination (IP) node to be reachable
> (at the creation time of the TNA/NTA device - instead of at the time
> of assigning a channel to the device like with Reverse-LAT)
> e.g. How to create the TNA device at startup time, when remote systems
> are not there yet?
>

I have not firmly tested this, but it seems as using:
$ telnet create <host> <port> <dev-no> /time=(noidle,recon=hh:mm:ss)
you get a TNA device that reconnects automaticly if the
connection is lost.

> *) Reverse-TELNET device gets lost/zombie if connection gets lost
> (instead of communication gets lost and can be re-assigned - like with LAT)
> e.g. how to autofix this, when a router reboots?
>

Same as above.

> *) Reverse-TELNET dissolves a node out of a group (like BIND/DNS multiple A RR)
> at device creation time - instead of at the time of assigning a channel
> to the device like with Reverse-LAT - means METRIC can't work like
> LAT service and/or LAT rating does)
>

True, but at least for us, we always connects to single points.

> *) Reverse-TELNET doesn't offer a wait for the connection to be established
> like what LAT-Queueing offers
>
> *) Reverse-TELNET doesn't offer a way to show where the TNA/NTA device
> is configured to - like LATCP SHOW PORT does.
>

$ tcpip sh ver

   HP TCP/IP Services for OpenVMS Alpha Version V5.5 - ECO 1
   on a COMPAQ AlphaServer DS20E 666 MHz running OpenVMS V8.2

$
$ Telnet/create <IP-address> 9100 6120 /prot=none
$
$ sh dev tna6120

Device                  Device           Error
  Name                   Status           Count
TNA6120:                Online               0

$ telnet
TELNET>  show device tna6120 /full
Device TNA6120:
     Access port name:       (none)
     Characteristics:        Autoconnect Permanent
     Connection attempts:        0 (tries)
     Connection interval:       15 (seconds)
     Connection timeout:         0 (seconds)
     Data high limit:          512 (bytes at VCI port)
     Data low limit:           256 (bytes at VCI port)
     Idle interval:             -1 (seconds)
     Idle timeout:               0 (seconds)
     Network device name:    (not connected)
     Protocol:               undefined (raw)
     Local address:          (not available)
               port:
     Remote address:         <IP-address>
               port:          9100
     Service type:           Outgoing
TELNET> [exit]

Is that what you asked for?
No local port since the detached app is not started at the moment.


 > No, wait, you *do* know, what you configured, right?)

Yes, we can always check with the COM startup files. :-)

> So, think again, if you really want to get rid of LAT...

That was thought over way before I came to this site! :-)
Today we have aprox 100 TNA devices setup as above and
just a handfull LTA devices left.

The use of LTA or TNA is 100% transparent to the applications.

The "get rid of LAT" is forced by new terms.servers with no LAT.

Regards,
Jan-Erik.
> just my 0.02
>