[syslinux] memdisk and iso

[Gene Cumm]

On Thu, Jun 6, 2013 at 11:58 AM, upen <upendra.gandhi at gmail.com> wrote:

>> This is sounding like dropped/intercepted packets.  Could we get some
>> details on the client (make/model of computer/motherboard, same for
>> NIC, PXE OROM details)?  Is it connected to the same physical switch
>> as the DHCP/TFTP server?  Any chance that the physical switch that the
>> client is connected to can perform port mirroring to see what is
>> received?
>
>
> DHCPD and TFTP server on Redhat 5.9 running as Virtualbox guest.
>
> 00:00.0 Host bridge: Intel Corporation 440FX - 82441FX PMC [Natoma] (rev 02)
> 00:01.0 ISA bridge: Intel Corporation 82371SB PIIX3 ISA [Natoma/Triton II]
> 00:01.1 IDE interface: Intel Corporation 82371AB/EB/MB PIIX4 IDE (rev 01)
> 00:02.0 VGA compatible controller: InnoTek Systemberatung GmbH VirtualBox
> Graphics Adapter
> 00:04.0 System peripheral: InnoTek Systemberatung GmbH VirtualBox Guest
> Service
> 00:07.0 Bridge: Intel Corporation 82371AB/EB/MB PIIX4 ACPI (rev 08)
> 00:08.0 Ethernet controller: Advanced Micro Devices [AMD] 79c970 [PCnet32
> LANCE] (rev 40) <----This is the one that is connected to Internal virtual
> switch on the server side.
>
> Client is also a Virtualbox guest.
> Intel UNDI - PXE-2.1
> 1997-2000 Intel corporation
> Network adapter: Intel pro/1000 T server(82543GC)
>
> I don't think how I can do port mirroring on this veritual switch but I am
> attaching another file tcpdump o/p and screenshot of what I see.

I think the RHEL guest or the host's interface to this network with
its NIC in promiscuous mode would suffice.

>> Any chance you could try manually copying pxelinux.0, lpxelinux.0,
>> ldlinux.c32, libcom32.c32, libutil.c32, libgpl.c32 and vesamenu.c32
>> from a freshly extracted copy of the tar (without running make at
>> all)?
>
>
> I did this some time back and then did the tcpdump and the screenshot I
> mentioned above and is attached here.

Thanks.  I'm still trying to see if there's any way to translate that
to PCAP format (ie tcpdump's -w _file_ option).  Using tcpdump with -A
I presume?

>> I presume using pxelinux.0 showed no errors such as this (aside from
>> slow TFTP transfer speed)?
>
>
> Yes that's correct. When I change my dhcpd.conf to load pxelinux.0 instead
> of lpxelinux.0, all works fine except ofcourse the ISO doesn't load via http
> , saying file not found which I think is expected being usage of pxelinux.0

Except that you're inside iPXE so I'd expect this to work if the iPXE
OROM has HTTP enabled (which is sounds like it's not).

>  /tftpboot/linux-install/pxelinux.cfg/C0A80058
> prompt 0
> timeout 600
>
> # Set-up menu as default
> DEFAULT vesamenu.c32
> PROMPT 0
>
> # Menu config
> MENU TITLE PXE Boot Menu
> MENU BACKGROUND iit.png
>
> label local
>   localboot 0x80
>
> label linux
> MENU LABEL Install RHEL6
>   kernel rhel6client/linux
>   append initrd=rhel6client/initrd.img ramdisk_size=14532 ks=nfs:NFS
> server:/ks/ks-rhel6.cfg ext4
>
> label ^-----freedos
>   MENU LABEL FreeDOS
>   kernel memdisk
>  # append initrd=msdos/FreeDOS-1.1-USB-Boot.img
>   append initrd=msdos/freedos
>
> ##THIS is MY CONCERN, loading this ISO via HTTP.
> LABEL hiren
> MENU LABEL HIREN
> LINUX memdisk
> INITRD http://192.168.0.100/hiren.iso
> APPEND iso
>
>
> Thanks for continuous help! I really appreciate it!!
>
> I am trying this on virtual machine to prepare for actual physical machine.
> Actualy physical machines is where the loading of iso took time.

Always good to test like this.

--
-Gene