From: Tony Dinh <mibodhi@gmail.com>
To: Fiona Klute <fiona.klute@gmx.de>
Cc: u-boot@lists.denx.de
Subject: Re: [PATCH v2 1/2] doc: Detailed example for netconsole setup
Date: Thu, 16 May 2024 12:28:36 -0700 [thread overview]
Message-ID: <CAJaLiFw1BD6rtMd8E3eejM62YY9W+YA9fmP9FGkiN1KE0fwgZw@mail.gmail.com> (raw)
In-Reply-To: <20240516104245.2075748-1-fiona.klute@gmx.de>
Hi Fiona,
On Thu, May 16, 2024 at 3:43 AM Fiona Klute <fiona.klute@gmx.de> wrote:
>
> This adds details that I would have liked to have readily available,
> in particular how to activate the network interface before enabling
> netconsole, and how to integrate netconsole so you can use the U-Boot
> prompt.
>
> Signed-off-by: Fiona Klute <fiona.klute@gmx.de>
> ---
> Changes in v2:
> * Include stderr redirection
> * Use 4 spaces instead of tabs for code block to avoid overflowing
> lines
>
> doc/usage/netconsole.rst | 33 ++++++++++++++++++++++++++++++++-
> 1 file changed, 32 insertions(+), 1 deletion(-)
>
> diff --git a/doc/usage/netconsole.rst b/doc/usage/netconsole.rst
> index 2aa3b9ccc5..647f0c220b 100644
> --- a/doc/usage/netconsole.rst
> +++ b/doc/usage/netconsole.rst
> @@ -18,7 +18,9 @@ broadcast address and port 6666 are used. If it is set to an IP
> address of 0 (or 0.0.0.0) then no messages are sent to the network.
> The source / listening port can be configured separately by setting
> the 'ncinport' environment variable and the destination port can be
> -configured by setting the 'ncoutport' environment variable.
> +configured by setting the 'ncoutport' environment variable. Note that
> +you need to set up the network interface (e.g. using DHCP) before it
> +can be used for network console.
>
> For example, if your server IP is 192.168.1.1, you could use::
>
> @@ -107,3 +109,32 @@ as follows:
>
> Note that unlike the U-Boot implementation the Linux netconsole is
> unidirectional, i. e. you have console output only in Linux.
> +
> +Setup via environment
> +---------------------
> +
> +If persistent environment is enabled in your U-Boot configuration, you
> +can configure the network console using the environment. For example::
> +
> + => env set autoload no
> + => env set hostname "u-boot"
> + => env set bootdelay 5
> + => env set nc 'dhcp; env set stdout nc; env set stderr nc; env set stdin nc'
> + => env set ncip 192.168.1.1
> + => env set preboot "${preboot}; run nc;"
> + => env save
> + => reset
> +
> +``autoload no`` tells the ``dhcp`` command to configure the network
> +interface without trying to load an image. ``hostname "u-boot"`` sets
> +the hostname to be sent in DHCP requests, so they are easy to
> +recognize in the DHCP server log. The command in ``nc`` calls ``dhcp``
> +to make sure the network interface is set up before enabling
> +netconsole.
> +
> +Adding ``nc`` to ``preboot`` tells U-Boot to activate netconsole
> +before trying to find any boot options, so you can interact with it if
> +desired.
> +
> +``env save`` stores the settings persistently, and ``reset`` then
> +triggers a fresh start that will use the changed settings.
> --
> 2.43.0
>
Just for information, if the board uses static IP then the example
would be slightly different. I usually use static IP and ping the
netconsole server to make sure it is up. However, I think this DHCP
example is good enough to show how to prepare and activate netconsole.
Reviewed-by: Tony Dinh <mibodhi@gmail.com>
All the best,
Tony
next prev parent reply other threads:[~2024-05-16 19:28 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-05-16 10:42 [PATCH v2 1/2] doc: Detailed example for netconsole setup Fiona Klute
2024-05-16 10:42 ` [PATCH v2 2/2] doc: Update netconsole examples, mention stderr Fiona Klute
2024-05-16 19:20 ` Tony Dinh
2024-05-16 19:28 ` Tony Dinh [this message]
2024-05-18 11:05 ` [PATCH v2 1/2] doc: Detailed example for netconsole setup Fiona Klute
2024-05-18 19:57 ` Tony Dinh
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