I was bitten lately by a problem of chaning passwords for users on a NIS master running RHEL 3. The actual error was
RPC: Can’t encode arguments
The password has not been changed on <nis master>.
passwd: Failed preliminary check by password service
I could not easily find anything on google about it. It took a while to figure out, so for reference I document my fix here. I merely removed the word ‘nis’ from /etc/pam.d/system-auth, and that seems to have solved the issue. It has worked previously with that word, so why it started to fail is beyond me, but who cares anyway.