Following files are required for  Linux user management.
/etc/passwd – contains various pieces of information for each user account
/etc/shadow – contains the encrypted password information for user’s accounts and optional the password aging information.
/etc/group – defines the groups to which users belong
/etc/gshadow – group shadow file (contains the encrypted password for group)
The following error ” The user database cannot be read. This problem is most likely caused by mismatch between /etx/password and /etc/shadow or /etc/group and /etc/gshadow. The program will …

Read On »