I'm trying to kickstart via nfs.  At the syslinux boot prompt, I type

linux ks=nfs:slserver.privnet:/SL/51/ks/standalone

The slserver logs an authenticated mount request, so it's accepted the 
request and offered the share.  But, the anaconda installer fails to 
register the offer and suggest I continue with an interactive install.  On 
screen 3, I see the following logged:

INFO   : doing kickstart... setting it up
INFO   : url is slserver.privnet:/SL/51/ks/standalone
INFO   : file location: nfs://slserver.privnet:/SL/51/ks/standalone
ERROR  : failed to open /tmp/mnt/standalone: Permission denied
ERROR  : failed to copy file to /tmp/ks.cfg

I've done NFS installs since RedHat 6.  Most times when it failed it was 
usually an NFS problem.  And I suspect this is the case here.  Perhaps some 
NFS4 weirdness?  I'd appreciate suggestions on how to proceed.