OPNsense Forum

I am trying to get the serial console to function. I have enabled it as secondary console, set the speed as 115200, and have set " Use USB-based serial ports " as enabled.

I then have have joined two USB to serial converter (tripp-lite u209-000-r) with a null modem (https://www.amazon.com/dp/B075XGRLXW/ref=cm_sw_em_r_mt_dp_AH3V8N07GZY398GQJYQA?_encoding=UTF8&psc=1) in the middle. This should work correct?

I my Linux system I then type:

# minicom -b 115200 -D /dev/ttyUSB0

I press the enter key a few times but only have a blank screen.  :(

from my Linux host dmesg shows.

[596342.276400] usb 1-2: pl2303 converter now attached to ttyUSB0

dmesg form the OPNsense firewall

ugen0.4: <Prolific Technology Inc. USB-Serial Controller D> at usbus0
uplcom0 on uhub0
uplcom0: <Prolific Technology Inc. USB-Serial Controller D, class 0/0, rev 1.10/3.00, addr 7> on usbus0

OPNsense /etc/ttys shows:
# Serial terminals
# The 'dialup' keyword identifies dialin lines to login, fingerd etc.
ttyU0 "/usr/libexec/getty 3wire.115200" vt100 onifconsole secure
ttyU1 "/usr/libexec/getty 3wire.115200" vt100 onifconsole secure
ttyU2 "/usr/libexec/getty 3wire.115200" vt100 onifconsole secure
ttyU3 "/usr/libexec/getty 3wire.115200" vt100 onifconsole secure
# Dumb console
dcons "/usr/libexec/getty std.9600" vt100 off secure

This is the motherboard in use on the OPNsense firewall and I am running v20.7.2
https://www.asrock.com/MB/Intel/H470M-ITXac/index.asp

Thank you.

Can you print the output of:

# ls /dev/ttyU*

Maybe init needs a bit of a jolt if you plug the USB into a running system:

# kill -HUP 1


Cheers,
Franco

Thank you franco.

# ls /dev/ttyU*
/dev/ttyU0 /dev/ttyU0.init /dev/ttyU0.lock

I have unplugged the USB serial converter and plugged it back on both systems and ran

# kill -HUP 1

on both systems too.  ;)


There was no change to the issue.

Here are the minicom settings on the Linux system

+-----------------------------------------------------------------------+                           
| A -    Serial Device      : /dev/ttyUSB0                              |                           
| B - Lockfile Location     : /var/run                                  |                           
| C -   Callin Program      :                                           |                           
| D -  Callout Program      :                                           |                           
| E -    Bps/Par/Bits       : 115200 8N1                                |                           
| F - Hardware Flow Control : No                                        |                           
| G - Software Flow Control : No                                        |                           
| H -     RS485 Enable      : No                                        |                           
| I -   RS485 Rts On Send   : No                                        |                           
| J -  RS485 Rts After Send : No                                        |                           
| K -  RS485 Rx During Tx   : No                                        |                           
| L -  RS485 Terminate Bus  : No                                        |                           
| M - RS485 Delay Rts Before: 0                                         |                           
| N - RS485 Delay Rts After : 0                                         |                           
|                                                                       |                           
|    Change which setting?         


Update
To test the cables I shorted out pins 2 and 3 per:
https://forum.opnsense.org/index.php?topic=15417.msg85417#msg85417
and reference:
https://knowledge.ni.com/KnowledgeArticleDetails?id=kA03q000000YFtECAW&l=en-US

And I was able to see the text I typed, so the cables are not the issue.

Update part 2
I tested on the loopback on the firewall too

# cu -l /dev/ttyU0
Connected
la;as;dfas

I got this working somewhat, I have to change "onifconsole" to "on".

change from:
ttyU0   "/usr/libexec/getty 3wire.115200"       vt100   onifconsole secure

change to:
ttyU0   "/usr/libexec/getty 3wire.115200"       vt100   on secure

So now I have two questions.

How do I make this persistent so that it survive a reboot?

What does "onifconsole" do vs. "on"?

I actually found another setting to add to the confusion, "onifexists".

Any thought on how to make this persistent across reboots?

How can I make this persistent?

If I change the line that has "ttyU0" in /etc/ttys from "onifconsole" to "on", it works great. But is will not stay if the system is rebooted.

change from:
ttyU0   "/usr/libexec/getty 3wire.115200"       vt100   onifconsole secure

to this:
ttyU0   "/usr/libexec/getty 3wire.115200"       vt100   on secure

and then restart init:
# kill -HUP 1

You can now see that the console is running:
# ps | grep getty
98163  0  R+   0:00.00 grep getty
95361 U0  Is+  0:00.00 /usr/libexec/getty 3wire.115200 ttyU0

Trading a fix for a ticket https://github.com/opnsense/core/issues/new?assignees=&labels=&template=feature_request.md&title=

I don't mind pinning USB console option to "on" instead of "onifconsole".


Cheers,
Franco

Thank you Franco, a ticket has been submitted.

https://github.com/opnsense/core/issues/4849