Reverse Telnet TNA Device

[Hal Kuff]

Hi, sorry to do Back to the Future.. but I know how to create a service on a DS900 to expose a port.. how do I get to the port (10.10.10.10 port 2010) for say port 10 on the server from a program on the OpenVMS system? Where does the TNA mapping take place? Basicaly we have outbound LAT modems and need LAT to go away...

[Jon Pinkley]

Hal,

Are you using the DS900 still? I would try connecting to tcp port 30xx the ip address associated with the terminal server, where xx is the port #. I.e. to connect to async port 5 on the DS900, connect to tcp port 3005. You have to have the port configured for remote access.

Why the need to have LAT go away? Are there routers between the terminal server and the OpenVMS system? Does there need to be (distance, etc.)?

Jon

[John Gillings]

Hal,

Telnet doesn't work like LAT. Although you can create a TNA device in much the same way as you create a LAT application port, you can't just open it from an application. I've never quite understood the reasons for this, but that's all academic. Banging your head against that brick wall won't help.

One (ugly) way around this uses the pseudo terminal interface. You have a process between your application and the network, which can be fed the appropriate TELNET commands to make the required connection. You can then communicate with an FTA device, just like you're currently communicating with an LTA device. The cost is an extra process per port.

I've got some sample code that does this, if you're interested.

[marsh_1]

alternatively you can spool the tna device to the old lat device.

[Hal Kuff]

Hi, great input (no pun)... basically this is a legacy application that is run from a command file by a vendor at login and then dials back a number tied to their account and sends product labels to a bar code printer conencted to a mode... low tech but has worked for 20 years... interested in 'spooling to the LTA from TNA'... that work?

[marsh_1]

hi,

sorry meant spool the lta device to a telnetsym print queue set up in this instance to point to - /on:"10.10.10.10:2010" -.
but these were set lta devices known to our app going to decserver ports no modems involved, don't how your application does it.
you can try spooling direct to a tna device i got variable results when i tried it.

HTH

[Volker Halle]

Hal,

did you check the $ TELNET/CREATE_SESSION command ? It is supposed to create a TNA device and map it to an IP-port on the DECserver.

Volker.

[Volker Halle]

Hal,

consider to have a look at this thread:

http://forums11.itrc.hp.com/service/forums/questionanswer.do?threadId=1096598

Volker.

[Hakan Zanderau ( Anders]

Maybe I'm sticking out my neck here......

If your application uses hardcoded LTAdevices.
Wouldn't a logical name take care of the redirection from LTA to TNA +

Create a TNA-device and remap the LTA-device

$ DEFINE/SYS LTA1: TNA1:

Hakan

[marsh_1]

hal,

we did ours like this

$INIT/QUE/PROC=TCPIP$TELNETSYM/RETAIN=ERROR/RECORD_BLOCKING /SCHEDULE=NOSIZE/DEF=(noburst,nofeed,noflag,notrail) /ON:"'decserver_ip_host_name':'ip_port'" 'que_name'

$set dev 'lta_dev_name':/spooled='telnetsym_que

with these two tcp logicals set

$DEFINE/SYSTEM TCPIP$TELNETSYM_IDLE_TIMEOUT "0 00:00:30.00"
$DEFINE/SYSTEM TCPIP$TELNETSYM_RETRY_INTERVAL "0 00:00:30.00"

example tna device creation

$TELNET/CREATE_SESSION/TIMEOUT=(NOIDLE,RECONNECTION=0:0:30) 'ip_host_name' 'port' 'tna_device_number'

HTH