Ok, got it: in  NFSROOT i changed 686 to 468.
Now i've getting a 486 kernel in /srv/tft and can install this old pc's.
Just need to figure out how /srv/tftp/fai/pxelinux.cfg/default can detect a 
amd64 or 386 or 386-non-pae cpu
gd


> we followed this wiki entry to install both amd-64 and i386 from the same
> fai install. It works well for us.
> http://wiki.fai-project.org/wiki/FAI_Cross-architecture
> 
> David Dreezer
> Social Strata, Inc.
> 
> On Sep 11, 2013, at 11:27 AM, linux-service.be bvba <[email protected]> 
> wrote:
> > In order to install older machines i added a i386 nfsroot.
> > But making this nfsroot fai is putting a pae initrd and vmlinuz in my
> > /svr/tftp for booting. Some clients cannot be boot with a pae kernel.
> > 
> > How can i prevent make nfs root for taking the pae kernel?

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