Password expiration:
Debian/Ubuntu/Red Hat
edit /etc/login.defs
PASS_MAX_DAYS 90
PASS_MIN_DAYS 0
PASS_MIN_LEN 8
PASS_WARN_AGE 7
Password History:
Debian/Ubuntu/Red Hat
Create the password history file and secure it:
sudo touch /etc/security/opasswd
sudo chown root:root /etc/security/opasswd
sudo chmod 600 /etc/security/opasswd
Debian/Ubuntu
edit /etc/pam.d/common-password
comment out
password requisite pam_unix.so nullok obscure md5
and uncomment
password required […]