Re: [Solved] Re: installed new kernel, but lost internal network
On Sun, Dec 07, 2003 at 02:36:09AM -0500, H. S. wrote:
> H. S. wrote:
> >Hi,
> >
> >I am doing masquarading using my Debian machine running Sarge. Earlier I
> >was running the default kernel that comes with Woody (2.4.18-bf14 or
> >something). Today I upgraded to the new kernel:
> >/var/log# apt-get -u install kernel-image-2.4.22-1-686 kernel-doc-2.4.22
> >kernel-headers-2.4.22-1 kernel-pcmcia-modules-2.4.22-1-686 pcmcia-cs
> >hotplug usbutils fxload hotplug-utils
> >
> >
> >And after this, I lost one of the NICs. I have two NICs, one is
> >192.168.0.1 connected to the ADSL moden, and the other is 192.168.0.2
> >connected to the internal LAN. So when I booted into the new kernel,
> >the second NIC RLT8139 was not detected. But when I did pppoeconf, it
> >listed only 1 NIC and asked if I had more which were not detected. I
> >said Yes, and it hen allowed me to install the module for the RLT NIC.
> >And after that it reported 2 NICs fine.
> >
> >So after configuring ppp0, I could browse the net, but my internal LAN
> >machine can't. I can't even ping that machine. I am running the same
>
> <snipped>
>
>
>
> Okay, I know what I was doing wrong, or what was going wrong without my
> actually doing it :)
>
> I extracted the bz2 kernel source archive in /usr/src and to prepare for
> a compilation, I copied my config-2.4.18-bf2.4 from /boot to kernel
> source directory (in my case it was kernel-source-2.4.22-hs1/). I
> assumed this would give me the same configuration as I had in my
> previous kernel. It was not so. I had to manually enable ip_forwarding,
> nat filtering, and all the related features in the menuconfig interface.
> These features were enabled in my older kernel, so I would guess
> something has changed between the kernel versions and just copying the
> old config file is not enough, it has to be hand edited to make sure all
> the options are set correctly as desired -- cannot avoid spending that
> half an hour going through that ncurses gui afterall :(
>
> I did that (since everything else was working, I figured it *had* to be
> the kernel) and my network is working perfectly.
>
> I wonder why nobody could suggest this. Nobody has encountered this
> before? Or nobody does masquarading with Debain (extremely unlikely I
> would guess, but possible)? :)
>
> Anyway, I hope this report helps someone else facing this problem,
> ->HS
>
I think that you were caught by a problem of which many are unaware,
and a few think too obvious to mention. Namely, between minor version
numbers of the kernel, the names and organization of config parameters
can change. It is always a good idea to use an existing .config that
you like as a starting point when building a new kernel. But, if you
are using a different source set from the one that was used with you
starting point .config, you really should use make oldconfig to catch
name changes and such. I think the instructions that come with the
kernel source say as much, but it may not be prominent enough to have
caught your eye.
When working with the kernel, I am very cautious. If I think I need to
do a build for whatever reason, I first try to build the kernel that I
think I already have, and make sure that my trial build kernel does
all the same things as my existing kernel, and in the same way. Then,
I know I have a proper build environment up and running, and a proper
starting point for modification. Then I start mucking about with
changes.
My 2 cents.
--
Paul E Condon
pecondon@peakpeak.com
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