Re: USB-serial adapter suggestions needed

Here's another example of a spontaneous disconnect, followed by
brining the ssh session back up and re-starting tip. The USB end
of the link is a 14-release Pi3 on the local network, so it does
not see ssh door-knocking. The serial console display is on a host
which is on the public Net and so does see frequent ssh attacks

login: 
login: Login timed out after 300 seconds
Dec 26 17:56:56 www login[8694]: 1 LOGIN FAILURE ON ttyu1

FreeBSD/arm64 (www.zefox.org) (ttyu1)

login: 

FreeBSD/arm64 (www.zefox.org) (ttyu1)

login: 

FreeBSD/arm64 (www.zefox.org) (ttyu1)

login: client_loop: send disconnect: Broken pipe
bob@raspberrypi:~ $ ssh 192.168.1.10
Password for bob@pelorus:
Last login: Thu Dec 28 23:01:43 2023
FreeBSD 14.0-RELEASE-p4 (GENERIC) #0 releng/14.0-n265400-4edf3b80733e: Wed Dec 27 20:21:26 PST 2023

Welcome to FreeBSD!

Release Notes, Errata: https://www.FreeBSD.org/releases/
Security Advisories:   https://www.FreeBSD.org/security/
FreeBSD Handbook:      https://www.FreeBSD.org/handbook/
FreeBSD FAQ:           https://www.FreeBSD.org/faq/
Questions List:        https://www.FreeBSD.org/lists/questions/
FreeBSD Forums:        https://forums.FreeBSD.org/

Documents installed with the system are in the /usr/local/share/doc/freebsd/
directory, or can be installed later with:  pkg install en-freebsd-doc
For other languages, replace "en" with a language code like de or fr.

Show the version of FreeBSD installed:  freebsd-version ; uname -a
Please include that output and any error messages when posting questions.
Introduction to manual pages:  man man
FreeBSD directory layout:      man hier

To change this login announcement, see motd(5).
You can prevent the removal of a ZFS snapshot by using the hold subcommand.
For example, to prevent the snapshot called milestone from deletion, run the
following command:

# zfs hold milestone_hold mypool/projects@my_milestone

The "zfs holds" command will list all current snapshots that are protected
this way (-r for a recursive list):

# zfs holds -r mypool

The TIMESTAMP column in the output of the above command is from when the
hold was created, not the snapshot it holds. The "zfs destroy" command will
echo a "dataset is busy" message on the console when it encounters a hold.
Use "zfs release" to release the hold on the snapshot:

# zfs release milestone_hold mypool/projects@my_milestone

		-- Benedict Reuschling <bcr@FreeBSD.org>
bob@pelorus:~ % su
Password:
# tip ucom
Stale lock on cuaU0 PID=1312... overriding.
connected
Dec 26 2pts exce [enter typed, this looks like a log entry from the public host]
Password:        [but how did it get reflected back to that host as input?]
Login incorrect
login: 

It isn't surprising to see leftover data flushing into the USB end host
when tip opens the serial connection. It is surprising that the host at
the serial end of the line sees some of that data as input, at least to me.

Maybe I simply misunderstand ...... Does getty not flush input before asking
for a login and password? Is echo happening between tip sessions? 

Thanks for reading.

bob prohaska