topic Re: Terminal server in Operating System - OpenVMS

Terminal server

Sunil_uk — Mon, 12 Sep 2005 07:03:45 GMT

Can some one guide me to setup a terminal server DEC700 on TCPIP network and to drive a serial display device on terminal server port PORT_01.

Presently it is working on LAT.
The application program takes the logicals and drive the display.
following def is used in LAT startup to enable the lat port
lcp set port LTA0201: /node=tght01(host name of the terminal server) /port=port_1
Is there any simillar def for enableing it on TCPIP address.

Re: Terminal server

Ian Miller. — Mon, 12 Sep 2005 11:09:58 GMT

Does this help?
http://h71000.www7.hp.com/wizard/wiz_0919.html

Re: Terminal server

Ian McKerracher_1 — Mon, 12 Sep 2005 15:16:46 GMT

Hello Sunil,

Do these help as well?

http://h71000.www7.hp.com/wizard/wiz_1561.html

http://h18000.www1.hp.com/support/asktima/communications/CHAMP_SRC971111005057.html

Good luck,

Ian

Re: Terminal server

Michael Yu_3 — Mon, 12 Sep 2005 19:12:32 GMT

Hi Sunil,

This is the minimum you have to do.

On the DS700:-
LOCAL> set priv
password>
LOCAL> change internet address ip_address
LOCAL> change internet mask 255.255.255.0 (e.g.)
LOCAL> change telnet listener 2001 port 1 enable
LOCAL>

On the OpenVMS system:-
TELNET> create_session ip_address 2001
%TELNET-S-CRSES, Session created on TNAxx
TELNET> exit

$ sho dev tnaxx

Device Device Error
Name Status Count
TNAxx: Online 0

You should be able to use the TNAxx created.

Thanks and regards.

Michael

Re: Terminal server

Sunil_uk — Wed, 14 Sep 2005 04:02:44 GMT

Though I have set the telent listener port 2001 to port 1, the show port 1 still shows default protocol as LAT.

I am able to ping after configuring the IP address.

I did the following

Local>Change telnet listener 2001 port 1 enabled

Re: Terminal server

Michael Yu_3 — Thu, 15 Sep 2005 00:39:37 GMT

Hi Sunil,

After you set the telent listener port 2001 to port 1 and enabled it, you can see the telnet listener with the following.

LOCAL> show telnet listener 2001

You can connect to this port remotely from a host like the following.

$ telnet ip_address /port=2001

If port 1 is connected to a display, then anything you type will be displayed on the device connected to port 1.

If you establish the connection using the method in my last reply, like

On the OpenVMS system:-
TELNET> create_session ip_address 2001
%TELNET-S-CRSES, Session created on TNAxx
TELNET> exit

Then you can use the following DCL to write to the device TNAxx.

$ Open/read/write chan TNAxx:
$ write chan "testing"

The word testing should be sent to the display connected to port 1.

Whenever you have a connection to telnet port 2001, you can check the status and the counters of port 1 by

LOCAL> show port 1 status
LOCAL> show port 1 counter

Remember to close the channel.

$ close chan

Remember to free the telnet listener 2001 by the following.

TELNET> delete xx

Thanks and regards.

Michael

Re: Terminal server

Sunil_uk — Thu, 15 Sep 2005 03:50:39 GMT

Thank you all for the guidence. I could configure the port successfully. This Decserver port i will using perminantly to connect a display unit, which displays some numeric values send by my srever. There is pascal program which already running which uses LAT presently (device name used LTA0201). I should be able to replace this device bt TNA1, which I have created from the telnet session.Any suggetion on this?.

Thanks

Sunuil

Re: Terminal server

Michael Yu_3 — Fri, 16 Sep 2005 01:56:28 GMT

Hi Sunil,

It may be better to use a logical name inside the program. Then define the logical to point to the created TNAxx: device.

Thanks and regards.

Michael

Re: Terminal server

Sunil_uk — Tue, 20 Sep 2005 04:58:01 GMT

Do I need to create a different TCPIP socket
inorder to establish the link or the telenet session which I have cretaed (TNA1:) will take care of the tarnsmission?.

I need to create thsi terminal device in another theree more servers pointing to same port on the same terminal server.is it possible?.

When I tried it was giving time out error.

thank you
sunil

Re: Terminal server

Michael Yu_3 — Tue, 20 Sep 2005 18:02:46 GMT

Hi Sunil,

The telnet session created will take care of the transmission. You just use the device TNAxx as a normal terminal device.

You can connect to the same port on the same terminal server from different systems, but one at a time. This means that once a system has connected to port 1 of terminal server A, the other system will have to wait until the original telnet connection has terminated. In order words, you cannot have multiple simultaneous telnet connections to the same port of the same terminal server.

Hope the above is clear.

Thanks and regards.

Michael

Re: Terminal server

Sunil_uk — Wed, 21 Sep 2005 02:58:11 GMT

Thank you, I understood that,

But when I am trying to create a sessionfrom another system I am getting a time out error.

I tried tlenet create_session.

already one session I ahve created on another system as TNA1: and is showing on line.

DO I need to manully delete the session every time before creating the other one?.

Thank you

Sunil

Re: Terminal server

Volker Halle — Wed, 21 Sep 2005 03:36:10 GMT

Sunil,

it works the same way as with LAT. You can only have ONE existing session to a terminal server port at any time (either with using LAT or with using TELNET protocol).

If your LAT application only establishes the LAT session to the port to output a message and then disconnects (as e.g. the LATSYM print symbiont will do), you would have to do the same with TELNET.

LAT connects would also be queued on the terminal server and then automatically completed, when the current connection is finished. This does NOT work with TCPIP.

Volker.

Re: Terminal server

Sunil_uk — Wed, 21 Sep 2005 03:53:57 GMT

Thnak you,
I have triplicated system, where in one system will be the duty one and will be sending data to the telenet port cretaed.
But if this system goes down one of the other system will become duty and will stert sending the data. there is a pascal program running which does the data tarnsmission. But defining and creating the session will be done by VMS. and At a time only one session will be active..but the channel should be avalable for the other system, if there is failure on the first systm

Thank you
sunil

Re: Terminal server

Volker Halle — Wed, 21 Sep 2005 04:25:52 GMT

Sunil,

with LAT, this is more transparent, as the connection to the terminal server port will be established, once you start the first write to the LTA device.

With TELNET CREATE_SESSION, the IP session is created immediately, so you can't have all 3 systems create this session at the same time.

It may be possible to use:

TELNET> CREATE_SESSION /TIMEOUT=(NOIDLE, RECONNECTION=nn)

Creates a device that disconnects on deassignment and reconnects when data is written to it.

I can't test this, but I would assume, that you should be able to do:

$ TELNET/CREATE_SESSION /TIMEOUT=(NOIDLE, RECONNECTION=1) server-ip server-port
$ OPEN/READ/WRITE x TNAx:
$ WRITE x "Starting"
$ CLOSE x

and then the TELNET-session to the terminal-server-port should be disconnected (due to the implicit $DASSGN by the CLOSE). After these commands, you might be able to issue these same commands on the other systems.

Volker.

Re: Terminal server

Sunil_uk — Fri, 21 Oct 2005 04:55:05 GMT

Hi

The said option timeout is not avaialble in telenet/create_session.

Thank you

Sunil

Re: Terminal server

Volker Halle — Fri, 21 Oct 2005 05:02:46 GMT

Sunil,

the availability of the /TIMEOUT option will depened on your version of UCX or TCPIP, e.g. UCX V4.2 on VAX does not have this option.

Volker.

Re: Terminal server

Sunil_uk — Fri, 21 Oct 2005 06:31:25 GMT

Thank you

Sunil

Re: Terminal server

Sunil_uk — Tue, 25 Oct 2005 11:17:53 GMT

I have created multiple telnet listener on port 1 (like 2001, 2002 and 2003).is it possible with any option to have three sessions from three different systems?.

Thanks Sunil

Re: Terminal server

Volker Halle — Tue, 25 Oct 2005 11:38:48 GMT

Sunil,

as said before, it's my understanding, that you can only have ONE session to a DECserver port from any system at the same time (be it with LAT or TCPIP).

It 'seems' to work with LAT, as the LAT session is NOT established UNTIL the first WRITE operation to the LTA201: device is issued !

Your version of UCX creates the TELNET session immediately when executing the TELNET/CREATE_SESSION command, this fails on the 2nd and 3rd system, if the first system has already established a session to that port.

As a workaround, you might have to try the TELNET/CREATE_SESSION command on your standby nodes in a loop with an appropriate WAIT, if you get a device timeout. That way, you'll know, that once the TELNET/CREATE_SESSION succeeds, this node is the one with the connection established and ready to write to the display device...

Or - if the stand-by nodes KNOW when to become active - just issue the TELNET/CREATE_SESSION at that time, when you know that the original node has failed.

Volker.

Re: Terminal server

Jan van den Ende — Tue, 25 Oct 2005 11:54:05 GMT

Sunil ( & Volker)

I have MULTISESSION ENABLE set, and I am using ONE VT520 to (up to) 8 sessions on ONE port.
But: NOT to predefined ports.

I do not know if this is usefull for your requirements; if yes, then I will gladly find out the setup and post it.

Proost.

Have one on me.

jpe