[Dnsmasq-discuss] Weird TFTP Failure

[Geert Stappers]

On Wed, Jul 14, 2021 at 04:29:08PM -0700, Michael wrote:
> On 7/14/21 3:06 PM, Craig Perry wrote:
> > Hello,
> > 
> > I'm battling a little bit with a weird PXE Boot issue - i can pxeboot
> > ubuntu 20.04 just fine but not 21.04. When booting 20.04 (which works
> > just fine) the behaviour i see is:
> > 
> > 1. transfers vmlinuz kernel image via tftp - OK
> > 2. transfers initrd image via tftp - OK
> > 3. Kernel boots, mounts the initial ramdisk then that's the end of tftp
> > stuff, everything thereafter happens over http and it's fine
> > 
> > However, when booting 21.04, the behaviour i see is:
> > 
> > 1. transfers vmlinuz kernel image via tftp - OK
> > 2. transfers initrd image via tftp - FAILS, always near the end of the
> > file transfer
> > 
> > The 20.04's initrd is 80mb in size, 21.04's is 99mb.
> > 
> 
> Its been a long time since I have done any PXE builds, but I remember seeing
> something like this in the past.   So take my response with a grain of salt
> :)
> 
> 
> What PXE boot manager are you using? 

I recomment https://ipxe.org/
BootROM downloads (over TFTP) and starts iPXE executable.
iPXE downloads over HTTP or HTTPS  kernel & initrd and starts them.


> I believe in the pxelinux.cfg file
> ( or similar ) you typically set ramdisk_size=<blah> and that needs to have
> enough room to hold the initrd.   You might want to check to see if yours is
> big enough for the larger initrd.

Yes, be aware of RAM lay-out.



Groeten
Geert Stappers
-- 
Silence is hard to parse