I have a NIS master-slave setup and I would like to improve the password rules/complexity for it. Seems like if I introduce new rules to the NIS Master they are applicable only from there. What I mean: I want minimal password length of 9 characters. On the NIS master if I run 'passwd' it obeys this requirement. If I run 'yppasswd' it just go to the default 6 characters. If I use 'chage -d 0 user1' to force a user to change a password, the user is prompted only when login on the NIS Master. The user's old password is still good to login at NIS clients. All machines are running Ubuntu 9.10 or 10.04.
How I can strengthen yppasswd rules and make it warn users to change their passwords? Thank you all!