How to connect COM Port to the switch?

Question

I'm new to Ubuntu. I recently bought a PL2303 USB to Serial connector and had placed its driver PL2303.C to my Ubuntu 17.10.

I put the command 'lsusb', and it showed:

Bus 001 Device 002: ID 8087:8000 Intel Corp. 
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 003 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 002 Device 004: ID 8087:07dc Intel Corp. 
Bus 002 Device 003: ID 1bcf:28b4 Sunplus Innovation Technology Inc. 
Bus 002 Device 002: ID 138a:0011 Validity Sensors, Inc. VFS5011 Fingerprint Reader
**Bus 002 Device 005: ID 067b:2303 Prolific Technology, Inc. PL2303 Serial Port**
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

and when I checked the 'dmesg' command ==> dmesg | grep tty it shows:

[    0.000000] console [tty0] enabled
[   19.113237] usb 2-3: pl2303 converter now attached to ttyUSB0
[   25.449300] ttyS3: LSR safety check engaged!
[   25.449943] ttyS3: LSR safety check engaged!

But when I plug that serial to the console port of my switch (i used the original dongle, so dongle must be not an issue), it won't appear. I suspect the com port. but i already check it with the command ==> setserial -g /dev/ttyS[0123456789], it shows :

/dev/ttyS0, UART: unknown, Port: 0x03f8, IRQ: 4
/dev/ttyS1, UART: unknown, Port: 0x02f8, IRQ: 3
/dev/ttyS2, UART: unknown, Port: 0x03e8, IRQ: 4
/dev/ttyS3: No such device
/dev/ttyS4, UART: unknown, Port: 0x0000, IRQ: 0
/dev/ttyS5, UART: unknown, Port: 0x0000, IRQ: 0
/dev/ttyS6, UART: unknown, Port: 0x0000, IRQ: 0
/dev/ttyS7, UART: unknown, Port: 0x0000, IRQ: 0
/dev/ttyS8, UART: unknown, Port: 0x0000, IRQ: 0
/dev/ttyS9, UART: unknown, Port: 0x0000, IRQ: 0

how to set com port (/dev/ttyS0) in order to be able to connected to the switch? PLease advise

But your port is set to ttyUSB0. Why are you trying to set on ttyS*? — Terrance, Jan 16 '18 at 05:43
You don't. The port was detected at /dev/ttyUSB0 so that is what you use for the connection to the serial port. /dev/ttyS[0-9] are for the built on serial ports to the motherboard which you are not using. — Terrance, Jan 16 '18 at 05:53
how to configure /dev/ttyUSB0 port so I can connect it to my switch's console port? — Rangga Handoyo, Jan 16 '18 at 06:09
Use a program like putty to connect. See the answers in https://askubuntu.com/questions/592386/ubuntu-putty-and-serial-port — Terrance, Jan 16 '18 at 06:16
I did, but didn't work.. My Ubuntu version is 17.10, I use Minicom instead, but still failed to connect — Rangga Handoyo, Jan 16 '18 at 06:31
You really need to edit your question and put in all the steps you have done and all the error messages you are getting. BTW, I prefer putty for connections to serial. — Terrance, Jan 16 '18 at 06:32
I tried to install putty, but after install it, it didn't work. there's a crash title below: " Putty crashed with SIGSEGV in XGetDefault", how to resolve this? — Rangga Handoyo, Jan 16 '18 at 07:19
Oh yes, Ubuntu 17.10 now uses Wayland. So X apps might have an issue. Try logging into Ubuntu as XOrg https://askubuntu.com/questions/961304/how-do-you-switch-from-wayland-back-to-xorg-in-ubuntu-17-10 then try the putty again. Make sure you are also setting the correct speed for the serial connection. It may be 115200 or 19200 or 9600. — Terrance, Jan 16 '18 at 16:03
You're very welcome! I wrote it up as a quick answer to help others as well. Glad it is working for you! =) — Terrance, Jan 18 '18 at 14:15

score 1 · Answer 1 · answered Jan 18 '18 at 14:15

To use putty in Ubuntu 17.10, you need to launch Ubuntu in XOrg. Follow the following answer to launch XOrg: How do you switch from Wayland back to Xorg in Ubuntu 17.10?

Your USB Serial device is at /dev/ttyUSB0. Make sure that you are using that for your putty connection.

sudo putty /dev/ttyUSB0 -serial -sercfg 9600,8,n,1,N

Make sure that you set the speed correctly for the console connection to the switch. It might be 115200 or 19200 or 9600.

Hope this helps!

How to connect COM Port to the switch?

1 Answers1