On Mon, 7 Feb 2011, Floris Bos wrote:

...
>> Unless you have a special reason to have the interface named eth1, it may
>> be better to have it recognized as eth0 in the first place. We're now
>> generally using "ksdevice=link pci=bfsort" when kickstarting, which makes
>> the "primary" NIC (as seen by the BIOS/vendor) eth0 during installation on
>> all our servers which would otherwise recognize it as eth1, avoiding all
>> these problems.
>
> Well, that still requires the cable to be in the first port, which might be
> best practice, but is not always reality.
....

Have you tried using:

   ksdevice=bootif

that should tell it to use the interface that was used to PXE boot the 
installer - whichever interface that happens to be.

Using ksdevice=link is fine as long as only one interface has link since 
it will pick the first 'up' interface, but bootif should always be the 
interface you booted from - assuming that the PXE code correctly fills in 
the BOOTIF= variable on the kernel command-line...

At the risk of mentioning the name that I shouldn't, the following is from 
the RHEL6 install guide mentioning this option (it has been much the same 
for several releases):

   http://docs.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/6/html/Installation_Guide/sn-booting-from-pxe-x86.html
...

  Note — Multiple NICs and PXE installation

  Some servers with multiple network interfaces might not assign eth0 to
  the first network interface as the firmware interface knows it, which can
  cause the installer to try to use a different network interface from the
  one that was used by PXE. To change this behavior, use the following in
  pxelinux.cfg/* config files:

   IPAPPEND 2
   APPEND ksdevice=bootif

  These configuration options above cause the installer to use the same
  network interface the firmware interface and PXE use. You can also use
  the following option:

   ksdevice=link

  This option causes the installer to use the first network device it finds
  that is linked to a network switch. 
...

Not that I actually do this much 'cos we have a number of boxes where they 
have to PXE on one interface but we want to do the install on a different 
(faster) one (well we could fix-up the sysconfig/.../ifcfg-* files later 
but that is more hassle).

  -- Jon