Re: pppoe problems

Ah, this is how I first doorstopped a modem.  Based on a 2MB flash chip, the
largest filesystem you can put on the modem is 1376255 bytes.  The stock
actiontec flash file system is 1362944 bytes.  This leaves you 13311 bytes to
work with.  If you try and add anything over that, your going to have problems.
 I have a feeling that the way the flash code and memory mapping works, the
flasher probably wraps the memory location back to the beginning of the flash
overwriting the bootloader code in the process.  Check the file size of your
flash filesystem image.

Patrick M

--- john <john-k2rtHP/[email protected]> wrote:
> Hi Bruce,
> 
> Thanks for the response, see comments below
> 
> On Tue, 2004-04-20 at 13:25, Bruce D. Lightner wrote:
> > John,
> > 
> > > I would like to try to copy the binary to flash so that I do not have to
> > > load it from an nfs mount.  I attempted to add my binary to the
> > > romdisk.img and reflash, this always results in a doorstop modem (thanks
> > > to the usb cable hack I am able to recover)  Any ideas on how to
> > > accomplish this?  I'm not sure why simply adding a file to romdisk image
> > > is hosing the boot loader.  -John
> > 
> > Can you describe exactly how you are modifying the ROM file system 
> > (romdisk.img) *and* where you got a copy of "romdisk.img" to modify.
> > 
> 
> My copy of the romdisk.img and linuz came from the actiontec website
> back in October of 2003.  I bought this modem awhile ago with the
> intention of converting it into a firewall/dsl router.  Put in on the
> shelf and am now looking at finishing it up.  So far so good if I can
> get my binary copied on the filesystem.  The copy of kernel that I
> snagged from the actiontec website must be of the older variety because
> it supports nfs and has vi.
> 
> I am modifying the ROM file system by first mounting it as a loopback
> device, copying it, and then running genromfs to create a new one.
> I did this at first to modify my /etc/rc script to disable bridging and
> assign an ip address.  This method of changing the romdisk.img worked
> fine until i tried to add my ARM version of pppoe to the filesystem. 
> 
> I do all of this on a debian/woody box, using genromfs 0.5.1
> 
> 
> > This Wiki page talks about one way to do this...
> > 
> > http://www.embeddedlinuxinterfacing.com/wiki.php/ActiontecGplReleaseHowto
> > 
> Very nice, I am looking forward to trying out a new kernel.  Hopefully I
> can try this soon.
> 
> I will try to use your method of creating the romdisk and see what
> happens.
> 
> 
> > I entered this game late and therefore all the Actiontec modems I own have 
> > the "new", stripped-down kernel and ROM file system.  There is no NFS (or 
> > "vi") included.  I therefore tend to test new application programs using 
> > TELNET and TFTP.  You clearly have the "old" Actiontec firmware because 
> > NFS works for you.
> > 
> > Are you building your application program using the "new" source code 
> > release from Actiontec?  Mixing differeing kernels and application code 
> > builds under uClinux *can be* a problem, in my experience anyway. 
> > However, given that you tested using NFS, what you are describing does not 
> > make sense unless this is some kind of boot-up "scripting" problem.
> > 
> 
> It doesn't make sense to me either.  
> My "doorstop modem state" is when I plug in the modem and I see the
> power LED but I do not see a link light on the ethernet. (nothing at all
> being sent out the wire)  The only way I know to recover from this state
> is to use Patrick's usb cable hack.
> 
> 
> > How are you loading your modified ROM file system?  Can we assume that 
> > you using BOOTP to install the kernel and the modified ROM file system?
> > 
> > Console port output sure would be nice, to see exactly what's going on. 
> > The important question is this a "door stop" of the form that will not 
> > even BOOTP anymore?  Or are you using the USB cable recovery "trick" just 
> > because it's convenient?
> > 
> 
> Yes I put it into a state where it will not BOOTP anymore. 
> 
> The way I am loading my modified ROM file system is through tftp.  I can
> only do this if I can talk to the modem over the ethernet.  If the modem
> is hosed I usually use the usb cable hack to recover it and tftp a new
> image by talking to it on its default ip 192.168.0.1.
> 
> 
> binary
> put linuz linuz
> put romdisk.img romdisk.img
> put tiburon.rbt tiburon.rbt
> 
> > The form of "door stop" that won't BOOTP indicates a bad "kernel" which is 
> > corrupting the modem's flash.  (I've made plenty of these!)  If, on the 
> > other hand, you simply are not getting the PPP functionality that you 
> > expected because some shell script was not quite right, you have a very 
> > different problem.
> > 
> 
> I agree that this doorstop mode should be caused by a bad kernel, (or
> bad bootloader?)  Maybe bootloader is an area that is getting corrupted
> by my modified romdisk.img.  I am not modifying the kernel or sending a
> new bootloader so I am not sure what else explains it.
> 
> 
> > Out of curiosity, what "flavor" of Linux are you using?
> > 
> 
> I am a debian guy, debian woody or debian unstable.
> 
> Is there another way I can 
> > Best regards,
> > 
> > Bruce
> 
> Thanks -John
> 
> 
> __
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