From mboxrd@z Thu Jan 1 00:00:00 1970 From: Cong Wang Subject: Re: [PATCH v2] allow ifup bring up network manually even without netroot Date: Tue, 10 Jan 2012 15:41:14 +0000 (UTC) Message-ID: References: <20111230083858.GA13018@darkstar.nay.redhat.com> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: Sender: initramfs-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: Content-Type: text/plain; charset="us-ascii" To: initramfs-u79uwXL29TY76Z2rM5mHXA@public.gmane.org On Fri, 30 Dec 2011 at 08:38 GMT, Dave Young wrote: > For kdump we need scp vmcore to remote machine, the nic to be used is > not limited to netroot one. we need a feature for manually bringing up > network interface. Also it is useful for emergency shell with > ssh-client for recovery or test purpose > > I implement this by adding one argument to ifup script, user can use > `/sbin/ifup eth0 -m` to bring up eth0, note ifup will regard it a > manual operation for the nic specified in 1st argument if there's > the 2nd argument. > > If same nic is used for netroot the 2nd argument will be ignored, > in this case we will leave netroot bring up it automatically to > avoid side effect. And in this case hooks such as kdump will need to > execute after netroot mounted. > > `ifup eth0 -m` will create /tmp/net.eth0.manualup stamp file, > later dhclient-script can check this and pass $2 to netroot, > then netroot script will bring eth0 up > As we talked on IRC, we still need to discuss if this is really needed, from kdump perspective. If we need to invoke `ifup` by ourselves, then we also need to determine which NIC we should bring up, this will make kdump code larger. So, I hope, we can have some kernel cmdline (like ip=...) to tell dracut which NIC we want to bring up in the second kernel, provided by either ssh-client module or nfs module. Let's see what Harald thinks...