Set root=... in pxelinux.cfg instead of root-path DHCP option

[GoogleCodeExporter]

This is more of a hypothetical issue than a real one.

I want to set my root= parameter in the pxelinux.cfg file instead of
via the DHCP root-path option. I have multiple clients booting
different Linux versions, so I already have the machinery in place to
select a different pxelinux.cfg file for each...  And it is much
easier for me to edit those pxelinux.cfg files than it is to modify my
DHCP configuration to hand out different root-path options for each
client.

Now, since the "96xnfsroot" dracut module forces root=dhcp, I figured
setting root= in pxelinux.cfg would not work.  But guess what?  If I
do not set a root-path in my DHCP configuration, and I do set
"root=nfs:..." in my pxelinux.cfg configuration, everything still
works.

But I am worried that this works only by coincidence and may
break in the future.  Put another way, since root=dhcp is not what I
want, it feels a little "dirty" to be setting it.

Suggestion:  If root= is already set on the kernel command line, 96xnfsroot 
could leave it alone (instead of setting root=dhcp)?

Thanks once again for this excellent project.

Original issue reported on code.google.com by lopre...@gmail.com on 9 Apr 2012 at 5:59