How can I view console output over a remote session?

[Staab_Engineering]

"Enable Console Out" is a checkbox option for my cRIO-9066 in MAX. Does that only go over the serial port, or can I get it to output to TTY too? I tried opening a telnet session in PuTTY, but it was rejected. (Is there a telnet server on the device at all?)

[DAQjr]

Use putty to connect over SSH. That's Secure Shell and most likely what you're looking for. Be sure to enable the SSH server in the same startup settings where you enabled console out.

[BradM]

The "Enable Console Out" checkbox in MAX enables the serial console output for your 9066.

There is no telnet support, however an additional checkbox in either the MAX property page or the on-target Web Interface is the ability to enable the SSH server on the target. There are many ssh clients available for all desktop operating systems (e.g. PuTTY for Windows)

Keep in mind that, when enabled, remote access to your target is enabled and you should change the default password for the admin account, and be sure to keep this password safe and do not lose it (as doing so requires contacting NI for instructions on resetting the controller to default factory settings)

[BradM]

DAQjr wrote:

Use putty to connect over SSH. That's Secure Shell and most likely what you're looking for. Be sure to enable the SSH server in the same startup settings where you enabled console out.

Gah, got beat to the punch...

[BlueCheese]

Hi David!

That only goes through the serial port. On Linux-targets such as this you can also SSH into the target and "sort of" get a console there. I say "sort of", becuase it doesn't include and standard output from the LVRT process or kernel console prints. You can get kernel prints via the "dmesg" commands, but getting stdout from the LVRT process is a bit more complex. I've had to modify the LVRT init script and use "tee" to redirect the output to a log file. You can then do a "tail -f" from the SSH session to get that output live.

I'm sure some RT Linux gurus here might have some other suggestions as well, depending on what you actually want to do.

Eric

[Staab_Engineering]

Thanks, all. I already know about sshd; I wanted to watch console output over TTY, though. Using a serial cable for console output is impractical for our IT configuration.

I infer from all the response that my sub-question of whether telnet is available is "no".

[BlueCheese]

I dug up what I did in the past, probably because someone more Linux'y than me sent me the idea.

If you edit /etc/init.d/lvrt-wrapper and change the line:

"exec ./lvrt $ARGS"

to

"exec ./lvrt $ARGS | tee ~/lvrtoutput.txt"

you will then have the console output from anything in the LVRT process go to a file as well. Then from your SSH session, you can to "tail -f ~/lvrtoutput.txt" and see the output live.

[ScotSalmon]

I infer from all the response that my sub-question of whether telnet is available is "no".

Can you clarify your use case for a telnet server? We've intentionally left it out since its functionality is almost completely subsumed by sshd, which offers a more secure replacement.

[David_Staab]

The user case is no different than for SSH. I just wanted y'all to explicitly say whether or not you included a telnet daemon in your distribution. Just curious.