Re: [PATCH net-next 0/4] (no cover subject)

From: Breno Leitao
Date: Tue Dec 09 2025 - 12:47:26 EST


Hello Jakub,

On Tue, Dec 09, 2025 at 04:37:45PM +0900, Jakub Kicinski wrote:
> On Fri, 5 Dec 2025 02:21:08 -0800 Breno Leitao wrote:
> > 1) Have a binary in each machine:
>
> > 2) Send a ping directly to the console
>
> > 3) Using per-loglevel patchset.
>
> > 4) send messages only to netconsole (this patchset)
>
> I think I was alluding that another option (not saying that it's the
> best but IIUC your requirements it'd be the best fit)):
>
> 5) Add a keepalive configfs knob, if set to a non-zero value netconsole
> will send an empty (?) message at given interval
>
> Pros:
> - truly does not require a user binary to run periodically, netcons
> would set a timer in the kernel
> Cons:
> - does not provide the arbitrary "console bypass" message
> functionality

This is a good idea if we change it slightly. What about a "ping"
configfs item that send sit when I touch it?

Something as:

# echo 1 > /sys/kernel/configs/<target>/ping

And it would ping the host with a predefined "ping" message, and nothing
else.

That would work, for my current problem, honestly.

One drawback compared to a more flexible "send_msg" is that I don't have
complete flexibility on the message format. Thus, if I want to pass
extra information such as a Nonce, timestamp, host state, interface
name, health state, it will not be possible, which is fine for now,
given I am NOT planning to use it at this stage.

Thanks for the idea and discussion,
--breno