Software >> OS >> Unix >> Solaris >> 11 >> What are the fields in the /etc/passwd and /etc/shadow files

/etc/passwd

Sample:

    1--------:2:3---:4---:5---------------:6--------------:7--------
    webmaster:x:1001:1001:Domain Webmaster:/home/webmaster:/bin/bash

Fields:

    1. Username      : It is used when user logs in. It should be between 1 and 32 characters in length.

    2. Password      : An x character indicates that encrypted password is stored in /etc/shadow file.
                       Please note that you need to use the passwd command to computes the hash of a
                       password typed at the CLI or to store/update the hash of the password in /etc/shadow file.

    3. User ID (UID) : Each user must be assigned a user ID (UID). UID 0 (zero) is reserved for root and
                       UIDs 1-99 are reserved for other predefined accounts. Further UID 100-999 are
                       reserved by system for administrative and system accounts/groups.

    4. Group ID (GID): The primary group ID (stored in /etc/group file)

    5. User ID Info  : The comment field. It allow you to add extra information about the users
                       such as user’s full name, phone number etc. This field use by finger command.

    6. Home directory: The absolute path to the directory the user will be in when they log in.
                       If this directory does not exists then users directory becomes /

    7. Command/shell : The absolute path of a command or shell (/bin/bash). Typically, this is a shell.
                       Please note that it does not have to be a shell. For example,
                       sysadmin can use the nologin shell, which acts as a replacement shell for
                       the user accounts. If shell set to /sbin/nologin and the user tries to login
                       to the Linux system directly, the /sbin/nologin shell closes the connection.



/etc/shadow

  • usename           : matches username entry in /etc/passwd
  • password          : encrypted password, lock string *LK*, string NP, or empty
  • last changed      : number of days since 1/1/1970 when the password was changed
  • minimum           : number of days to pass before you can change the password
  • maximum           : number of days the current password is valid
  • warning           : number of days before password expiry to warn the user
  • inactivity        : number of days the account may remain inactive
  • expiration        : number of days since 1/1/1970 that the account will expire
  • flags (attempts)  : number of consequtive failed login (attempts)

 

Reference:

[1]  OCA Oracle Solaris 11 System Administration Exam Guide (Exam 1Z0-821)