You should try the ypserv rpm that is in the recent "beta for 4.4".

It is at 

ftp://ftp.scientificlinux.org/linux/scientific/40rolling/x86_64/SL/RPMS/

-Connie Sieh

On 
Mon, 
4 Sep 2006, Mark Whidby wrote:

> Hannon bulk mail wrote:
> > Hi, folks.  We recently installed SL 4.3 on a dual-Opteron system here:
> > 
> > # uname -a
> > Linux xxxxxxx.physics.ucdavis.edu 2.6.9-42.0.2.ELsmp #1 SMP Tue Aug 22 18:36:24 CDT 2006 x86_64 x86_64 x86_64 GNU/Linux
> > 
> > We set the system up to be an NIS server:
> > 
> >     yum install ypserv
> >     service ypserv start
> > 
> >     /usr/lib64/yp/ypinit -m
> > 
> > The system is, so far, the only NIS server for its group of client
> > systems.
> > 
> > The installation seemed to go as expected, but we encountered a problem:
> > after a few minutes the server would lose its ypbinding to itself,
> > effectively causing NIS to stop working.
> 
> This has been reported here already. Have a look at:
> 
> http://listserv.fnal.gov/scripts/wa.exe?A2=ind0605&L=SCIENTIFIC-LINUX-USERS&P=R1706&I=-3
>