Some Details on Format of /etc/shadow

Hi everyone,

I often used to wonder about the format of /etc/shadow file and with little research I came across some usefull information about it.So basically here I am going to list some of the details about the format of /etc/shadow file do read it carefully hope you will enjoy it 🙂
Test format


All fields are separated by a colon(:) symbol

User name : It is your login name
Password: It your encrypted password. The password should be minimum 6-8 characters long including special characters/digits
Last password change (lastchanged): Days since Jan 1, 1970 that password was last changed
Minimum: The minimum number of days required between password changes i.e. the number of days left before the user is allowed to change his/her password
Maximum: The maximum number of days the password is valid (after that user is forced to change his/her password)
Warn : The number of days before password is to expire that user is warned that his/her password must be changed
Inactive : The number of days after password expires that account is disabled
Expire : Days since Jan 1, 1970 that account is disabled i.e. an absolute date specifying when the login may no longer be used

The last 6 fields provides password aging and account lockout features.Password field must be filled.


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