Re: -current dropping ssh connections

From: Cheng Cui <cc_at_freebsd.org>
Date: Wed, 21 Jun 2023 19:26:52 UTC
>
> There don't seem to be any error messages on the console at all, the
> client
> session simply reports
> client_loop: send disconnect: Broken pipe
>

Have you tried SSH keepalive?
https://stackoverflow.com/questions/25084288/keep-ssh-session-alive

Best Regards,
Cheng Cui


On Wed, Jun 21, 2023 at 1:24 PM bob prohaska <fbsd@www.zefox.net> wrote:

> I've got a Pi4 running -current that seems to selectively drop ssh
> connections.
>
> Connections running a shell seem to stay up, but a session running tip to a
> usb-serial adapter (FTDI TTL232R-3V3) seems go away within a few hours.
> There don't seem to be any error messages on the console at all, the
> client
> session simply reports
> client_loop: send disconnect: Broken pipe
>
> Searches through /var/log/sshd_debug.log find many transactions between
> the ssh client and the -current target host, but none seem to be error
> messages; all are either connection reports or disconnects by user.
>
> This sort of behavior has been intermittent with aarch64 among both
> the Pi4 and a pair of Pi3s for some time, but now only the Pi4 is
> dropping connections.
>
> I've tried searching /var/log/sshd_debug.log for the keywords tip,
> ucom, the IP address of the NAT client used to connect and cuaU0.
> Are there other things worth looking for?
>
> Right now I'm using in /etc/rc.conf the line
> sshd_flags="-E /var/log/sshd_debug.log"
> which is already quite verbose. Is there a better
> option that emphasizes errors over normal traffic?
>
> Thanks for reading,
>
> bob prohaska
>
>
>
>