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I'm trying to remotely connect to a system via Bluetooth but am running into problems. Here's what I'm trying to do...

On the remote device I'd like to have the following running: rfcomm -r watch 0 3 getty -L {} 9600

What that does is: Watch on the bluetooth device "0" for an rfcomm connection on channel 3. When one occurs, run getty -L {} 9600 and replace the "{}" with the device created. (usually /dev/rfcomm0 in this case)

I then should be able to connect to the remote device by running on my laptop: rfcomm connect 0 11:22:33:44:55:66 3 (tells it to use device "0" to connect to the bluetooth address "11:22:33:44:55:66" on channel 3) I then should get a serial console on the remote device by typing screen /dev/rfcomm0.

The problem...

Everything should be working fine except NetworkManager on my laptop somehow "sees" the connection and tries to probe it as if it was a modem. It sends AT+GCAP strings and ~x�~ but the remote end is running getty and is expecting login credentials.

I'm able to get it to work by making the rfcomm0 connection first:

remote$  rfcomm -r watch 0 3
laptop$  rfcomm connect 0 11:22:33:44:55:66 3

wait about 60 seconds for the NetworkManger to stop probing /dev/rfcomm0

remote$  getty -L rfcomm0 9600
laptop$  screen /dev/rfcomm0 9600

However, in order to do this, I already need to have console access to the remote device in order to run the getty comamnd


So, is there any way to tell NetworkManager to ignore /dev/rfcomm or to tell it to not probe the device?

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There is a similar case with a solution that helped some but not all. See here:

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Welcome to Server Fault! Whilst this may theoretically answer the question, it would be preferable to include the essential parts of the answer here, and provide the link for reference. – Mark Henderson Feb 18 '13 at 3:07
I think the person was also hoping I had found an answer myself. I had seen that other page already when I tried finding an answer with Google. However, I can't keep disabling the Network/Modem Manager and rebooting just to do a quick command over the rfcomm serial. The best solution I've got so far is to "type really fast" in between the probing AT commands. :P Which is just enough for me to get by for the moment. – Tim Tisdall Feb 19 '13 at 14:06

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