Linux-User Profiles

User provisioning Files: 1 User information file/etc/passwd 2 Shadow file/etc/shadow 3 Group information file/etc/group

4 set of password files/etc/gshadow

1 User Information file/etc/passwd

1. User name
2. Password flag (x means the user has a password, the password is mapped to the/etc/shadow file,)
3. UID (User ID) (0: Super User 1-499: System User (System user also called pseudo user, used to start command, cannot log on and delete) 500-65535: normal user)
4. GID (user initial group ID)
5. User Description
6. Home directory (normal User:/home/user name Super User:/root)
7. The shell after login

Initial group: Refers to a group that a user has built on. Each user has only one initial group

[[email protected] ~]# cat/etc/passwd  root:x:0:0:root:/root:/bin/bash   Super User, with password, uid 0,gid for 0   Bin:x:1: 1:bin:/bin:/sbin/nologin   daemon:x:2:2:daemon:/sbin:/sbin/nologin  pseudo-user sbin:/ SBIN/SHUTDOWNSTACK:/VAR/RUN/AVAHI-DAEMON:/SBIN/NOLOGINTCPDUMP:X:72:72::/:/SBIN/NOLOGINSSHD:X:74:74: privilege-separated ssh:/var/empty/sshd:/sbin/nologinoprofile:x:16:16:special user account to being used by OProfile:/ Home/oprofile:/sbin/nologinChenna:x:500:500::/home/chenna:/bin/bash  General user chenkai:x:501:502::/home/ Chenkai:/bin/bash

You can change the UID of the configuration file to 0 instead of the normal user becomes superuser.

2 Shadow File/etc/shadow

1. User name
2. encryption password       (!! or * means no password, no login   For example, the pseudo-user is * or!!  )
3. Password Last modified      
4. Two-time password modification interval
5. password validity period       (changed to n days, is to force the user to change the password every n days)
6. The number of days before password modification expires
7. Grace days after password expires (0: Expires immediately after password expiration       -1: Indicates that the password will not expire permanently )
8. account Expiration Time   
9. reserved

[Email protected] ~]# Cat/etc/shadowroot:$$9psq/qiicntcgyce$9wag77jc2ljk1pgpddi1lsxjlyuyoggzyaind8z4ewcp/ MLHVW
/ur/n8d7if1uvvkiwshwfr3ijuqepigajv2/:17357:0:90:7:5::  
Super User
Bin:*:15513:0:99999:7:::sshd:!! : 17357:     .:::: oprofile:!! : 17357::::::
Pseudo user
Chenna:$6$ijk6ovcc$itrmzztt.nek5ahhffszyighdfoqblls2pacmbxjvzcwce.dak3osfadf8
G7dke0azz9xo5ihaql2vszrnplg/:17357:0:99999:7:::
Normal User


You can modify this profile by adding the password before encrypting it! Disable the password, you can lock the user

3 Set of information files/etc/group

1. Group name
2. Group password flag (→/etc/gshadow)
3. Gid
4. Additional users in the group

sshd:x:74:oprofile:x:16:slocate:x:21:chenna:x:500:brother:x:501:chenkai:x:502:

3 Set of password files/etc/gshadow

1. Group name
2. Group password
3. Group Administrator user Name
4. Group Attach User

sshd:!::oprofile:!::slocate:!::chenna:!::brother:!::chenkai:!::

Linux-User Profiles