Is this on openSUSE 11.3 machines ? Then it's probably NFS (causes a 3 minute delay, due to a config fault). that's bothering you. I cannot say anything about the NIS config. I use NIS a lot, yet have always configured NIS through the Yast modules.
The NFS trouble:
in /etc/nfsmount.conf change the line in red to the line in bold:
Please get back here with results. If you're interested, I can tell you how I configure NIS/NFS through Yast. AFAICS yours is becoming quite away from default.