From mboxrd@z Thu Jan 1 00:00:00 1970 From: Struan Bartlett Subject: Re: [PATCH v2] netconsole: Add tty driver Date: Wed, 2 Apr 2014 23:30:24 +0100 Message-ID: <20140402223024.GA12627@NewsNow.co.uk> References: <533B2F03.6060008@gmail.com> <201404022116.HIB82683.FOJMFFHVStOLOQ@I-love.SAKURA.ne.jp> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: linux-kernel@vger.kernel.org, schwab@linux-m68k.org, netdev@vger.kernel.org, davem@davemloft.net, nikolay@redhat.com, andy.shevchenko@gmail.com, gregkh@linuxfoundation.org, jiri@resnulli.us, joe@perches.com, alonid@postram.com To: Tetsuo Handa , mpm@selenic.com Return-path: Content-Disposition: inline In-Reply-To: <201404022116.HIB82683.FOJMFFHVStOLOQ@I-love.SAKURA.ne.jp> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On 02/04/2014 14:16, Tetsuo Handa wrote: > Struan Bartlett wrote: >> Adds tty driver to netconsole module. When module is loaded, >> creates /dev/netcon0 device and enables support for console=netcon0 >> kernel cmdline option, causing /dev/console output to be sent to >> /dev/netcon0. This allows startup/shutdown script output from >> headless platforms to be logged over (secure) network. > > Excuse me, but I think that the netconsole logging can work only during network > interfaces (e.g. eth0) are up. Did this patch description assume that the > network interfaces are up before the startup script is started and the shutdown > script is finished before the network interfaces are down? Yes it did. I hope I have clarified that in the v3 patch description. In practice, at least in a Debian environment: i) the netconsole module itself is generally capable of raising the network interface when it is loaded by the initramfs init script (which precedes all /etc/init.d/* scripts); ii) very little of consequence tends to happens during shutdown after networking is stopped; iii) equally, it is not usually problematic to disable the networking shutdown script, since it runs on platforms about to be rebooted or powered off. We do this by editing the Default-Stop LSB header in /etc/init.d/networking. > By the way, I uploaded a logger specialized for receiving netconsole messages > to http://sourceforge.jp/projects/akari/scm/svn/tree/head/branches/udplogger/ . Thank you. I'll check it out.