04_01 Linux User management commands (bottom)

User management:

useradd [option] USERNAME

-U UID USERNAME

-G GID

-G GID,... (Multiple additional groups comma separated)

-C "COMMENT" specifies annotation information

-d/path/to/somedirectory Specifying a directory

-S shell specifies the directory path of the shell

-m-k forcibly copying bash's configuration file by default is to copy the past

-m not to create home directory

-R Add a system user 1-499 system user cannot login system no home directory

/etc/skel Personal Bash configuration file

/etc/shells: Specifies the security shell that is available for the current system

The default ID number is the ID number +1 that currently exists

You can use the Echo $SHELL to view the shell you are using

Useradd-u user1     

Useradd-g Helloa user2 Add a user to a specified user group

Useradd-g MyGroup User3

Useradd-c "Tony blare"-d/home/blare user4

Tail-1/etc/passwd can see the last line

Useradd-s/sbin/nologin User5 not to use the shell

useradd-s/bin/tcshell using Tcshell  

Useradd-m User7

Environment variables

PATH

SHELL

Histsize

ID View user account properties

ID User1

ID is empty property of the currently logged on user

Id-u

-G

-G

-N

Finger User View account information

Timed task mail, etc.

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Userdel user1

User Delete user's home directory is not deleted

Userdel-r Username Delete User at the same time delete home directory

How to modify user account properties

Usermod

-U UID Change ID

-G GID reorganization must have existed beforehand

-G If the previous add-on group is removed before the addition of the specified new will overwrite the previous additional group

-a-g GID Append additional group does not overwrite

-C Modify Comment information

-D directory If the user is logged in with a new file modification, the original directory file cannot be accessed.

-d-m directory modifies home directory location and moves home directory files to the new home directory

-S Change shell

-L Switch User name

-L Lock Account

-U: Unlock Account

Usermode-u 2002 User3 Change ID

CHSH User: Modify the default shell for users

CHFN User Comment Information modified

Password management

passwd [USERNAME]

--stdin standard input password from standard

-L Lock user account lock

-U unlock Unlock

-N Minimum Password usage period

-D Delete User password

echo "Redhat" | passwd--stdin user3 Accept character Change password from pipe

passwd-d user3 clear user3 password blank password cannot log in

Pwck Checking user account Integrity

Group Management:

To create a group:

Groupadd

-G GID

-R added as System group

Groupmod

-G GID

-N GRPNAME Revision group name

Groupdel Deleting a group

GPASSWD setting a password for a group

NEWGRP GRPNAME <-->exit Switch New group--Exit

GPASSWD MyGroup Set Password

NEWGRP MyGroup Switch to a new group if you belong to a basic group that does not need to switch

Exit the newly logged in group

Useradd-r Apache System Group

Groupadd-r Nginx

change user Password expiration time

Chage

-d Specifies the last modification time

-E Expiration Time

-I: Inactive time

-m minimum term of use

-M maximum lifespan

-W Warning Time

This article is from the "Jiawu notes" blog, so be sure to keep this source http://jiawu.blog.51cto.com/9349234/1586770

04_01 Linux User management commands (bottom)