Force a user to change their password at next login
Tue 28 October 2014 by Mikhail BasovAIX:
pwdadm -f ADMCHG <username>
HP-UX, Solaris:
passwd -f <username>
RHEL 6:
passwd -e <username>
RHEL 5:
usermod -L <username> # lock user
chage -d 0 # set password expired
usermod -U <username> # unlock user
('chage' - change adge)