Connect to communication port of WWAN card using serial in Putty

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1

Hi Guys

I have a Sierra Wireless EM7455 WWAN (cellular) modem in my Dell Lattitude 5520 laptop. I have fedora36 running in it. When I try to connect to the communication port of WWAN via serial connection in Putty, it gives me a permission error. The WWAN card is enabled to AT mode. What am I doing wrong?

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2

Try to put your user in to the dialup group.

3

To add a little detail to what was said by @ilikelinux

If you do an ls -l /dev/ttyUSB2 it will show you the owner and group for the device. If the group is ‘dialout’ as I would expect, then the command sudo usermod -a -G dialout USERNAME should add that user to the group. After logging out then back in you should have access.

4

Thanks for the detailed explanation. I was using the f36 live media and for some reason the usermod command was not adding the user liveuser to the dialout group. I then, sudo into putty and managed to connect to the ttyUSB2 port.

5

It probably was adding the user to the group, but from the live media you cannot log out then back in and group changes only take affect with a new login. Logging in with ssh counts as a new login to that gave you access.