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"How to force every new user to change password at first login
For this change we need to change the default setting of useradd command.
[root]# vim /etc/default/useradd
Look for the line or just append the following line in the file.
Expire=0"
Ou
Você pode alterar a expiração da senha com usermod e isso reforçará a alteração da senha.
A. You can use any one of the following command to change user passwords upon the first login: [a] usermod command - Modify various user account properties including user password expiry information.
Ou
can set empty/null password and use passwd command to expire password. This will result into immediate password change for the first time.