Lpr and Rndis

[bong.mau]

Hi

Env: Windows 7 enterprise x64 (SP1 + convenience rollup kb3125574)

i'm able to succesfully print to lacal device usign lpr

this command works

lpr -S 127.0.0.1 -P HP filetoprint

when  i connect my laptop pc to internet using Android device USB tethering then lpr is unable to find printers 

i get the following message

Windows LPD ServerError: specified printer does not exist

i get the same message if i issue  "lpq -S 127.0.0.1 -P HP"

i spent a lot of time isolating this error ...it is due 100% to RNDIS interface activation ...as i deselect "usb tethering" in the smartphone, lpr starts working correctly .....

thanks in advance for the support  

Maurizio

[jaclaz]

127.0.0.1 is "self".

Do you have an IP address when tethered (that you have not when not tethering)?

i.e. if you run IPCONFIG /ALL when tethered and not tethered do you see any difference?

jaclaz

 

[bong.mau]

Hi Jaclaz

Thanks for the answer

Because the problem sounds STRANGE and hard to believe i create this batch file

@echo off
ipconfig  /all >rndis.txt
if %ERRORLEVEL%== 0 (
    lpq -S 127.0.0.1 -P HP >>rndis.txt
)        
if %ERRORLEVEL%== 0 (
    timeout /T 15
    ipconfig  /all >nocon.txt   
    lpq -S 127.0.0.1 -P HP >>nocon.txt  
 )

i launch the batch when Pc connect to internet via android usb tethering and i disconnect during timeout

i attach  rndis.txt and nocon.txt
as you can see when rndis is active lpq is unable to find the printer 

...mumble...mumble ....

 

rndis.txt nocon.txt

[jaclaz]

Yep, good  , what I suspect is not that the printer cannot be found, but rather that lpq wants the "real" IP address.

what happens (when you are connected) with a batch *like*:

@ECHO OFF
SETLOCAL
SET myLocalIP=
FOR /F "tokens=2 delims=:(" %%A IN ('TYPE rndis.txt ^|FIND "IPv4 Address."') DO ( 
SET myLocalIP=%%A
)
IF NOT DEFINED myLocalIP SET myLocalIP= 127.0.0.1
CLS
ECHO Local IP is%myLocalIP%
ECHO.
ECHO Press a key to run command:
ECHO lpq -S%myLocalIP% -P HP
ECHO.
ECHO or press CTRL+C to terminate the batch
ECHO.
PAUSE
lpq -S%myLocalIP% -P HP

Of course, you can (should) replace the 

TYPE rndis.txt

with

IPCONFIG /ALL

jaclaz

 

Edited June 28, 2020 by jaclaz

[bong.mau]

WORKS !!
JACLAZ...GREAT SUPPORT !!
Ciao ...Maurizio

[jaclaz]

4 hours ago, bong.mau said:

WORKS !!
JACLAZ...GREAT SUPPORT !!
Ciao ...Maurizio

Good .

Another happy bunny in the basket.

jaclaz