Linux Learning Commands Summary ⑦

#useradd命令: Set up user accounts and create a user's starting directory, using permissions is Superuser

[[Email Protected]_168_102_centos ~~]# ID testuid=502 (test) gid=502 (test)groups=502 ~]# Tail-n 1/etc/passwdtest:x:502:502::/home/test:/bin/bash

Useradd–u UID: Specify UID directly when creating user

[[Email Protected]_168_102_centos ~]# useradd-u 888~]# tail-n 1/etc/passwdtest_1:x:888:888::/home/ Test_1:/bin/bash

Useradd–g GID: Specify Gid,gid to be pre-existing when creating user

[Email protected]_168_102_centos ~]# useradd-g~]# tail-n 1/etc/passwdtest_2:x:889:500::/home/ test_2:/bin/~]# ID test_2uid=889 (test_2) gid=500 (Wanghan) groups=500~]# useradd-g 777  ' 777 ' does not exist

Useradd–g GID: Specify additional groups directly when creating a user, but the group must exist beforehand

[Email protected]_168_102_centos ~]# useradd-g~]# tail-n 1/etc/passwdtest_3:x:890:890::/home/ test_3:/bin/~]# ID test_3uid=890 (test_3) gid=890 (test_3) groups=890 (Test_3), (Wanghan)

Useradd–d: Specify the home directory when creating a user, and if this directory does not exist, you can create a master directory by using the-M option

[Email protected]_168_102_centos ~]# useradd-d/home/qidian-m test_6      ~]# tail-n 1/etc/passwdtest_6: X:893:893::/home/qidian:/bin/~]# ls/homeabc  ceshi  openstack  qidian  test  test_1  test_2  test_3  Wanghan

Description: –m: Forcing a user to create a home directory when creating a user

Useradd–m: Create user, but do not create home directory

[[Email Protected]_168_102_centos ~]# ls/homeabc  ceshi  openstack  qidian  test  test_1  Test_2  test_3  ~]# useradd-~]# tail-n 1/etc/passwdtest_7:x:895:895::/home/test_ 7:/bin/~]# ls/homeabc  ceshi  openstack  qidian  test  test_1  test_2  test_3  Wanghan

USERADD-C: Create user-specified annotated description, view in/ETV/PASSWD

[Email protected]_168_102_centos ~]# useradd-c wanghan test_9                                                 ~]# tail-n 1/etc/passwdtest_9:x: 897:897:wanghan:/home/test_9:/bin/bash

Useradd–s: Specify the default shell when creating a user, you should specify the shell that the/etc/shells file appears in

[Email protected]_168_102_centos ~]# useradd-' tcsh '~]#useradd-s/bin/~]# tail-n 1/etc/
   
    PASSWDTEST_10:X:898:898::/home/test_10:/bin/tcsh
   

#groupadd命令: Create a new group

[[Email Protected]_168_102_centos ~~]# tail-n 1/etc/grouphp:x:2001:

Groupadd–g GID: Create a new group and specify GID

[Email protected]_168_102_centos ~]# groupadd-g~]# tail-n 1/etc/groupwudi:x:~]#

#userdel命令: Delete user, home directory is reserved by default

[Email Protected]_168_102_centos ~]# Userdel test_9[[email protected]_168_102_centos~]# tail/etc/passwdtest_1:x:888:888::/home/test_1:/bin/bashtest_2:x:889:500::/home/test_2:/bin/bashtest_3:x:890:890::/home/test_3:/bin/bashtest_4:x:891:891::/home/abc:/bin/bashopenstack:x:892:892::/home/openstack:/bin/bashtest_6:x:893:893::/home/qidian:/bin/bashwanghan11:x:894:894::/tmp/wanghan:/bin/bashtest_7:x:895:895::/home/test_7:/bin/bashtest_8:x:896:896::/home/test_8:/bin/bashtest_10:x:898:898::/home/test_10:/bin/Tcsh[[email Protected]_168_102_centos~]# LS/homeabc ceshi openstack Qidian test test_1 test_10 test_2 test_3 test_8 test_9 Wanghan

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

[Email protected]_168_102_centos ~]# Userdel-R test_8[[email Protected]_168_102_centos~]# tail/etc/passwdtest:x:502:502::/home/test:/bin/bashtest_1:x:888:888::/home/test_1:/bin/bashtest_2:x:889:500::/home/test_2:/bin/bashtest_3:x:890:890::/home/test_3:/bin/bashtest_4:x:891:891::/home/abc:/bin/bashopenstack:x:892:892::/home/openstack:/bin/bashtest_6:x:893:893::/home/qidian:/bin/bashwanghan11:x:894:894::/tmp/wanghan:/bin/bashtest_7:x:895:895::/home/test_7:/bin/bashtest_10:x:898:898::/home/test_10:/bin/Tcsh[[email Protected]_168_102_centos~]# LS/homeabc ceshi openstack Qidian test test_1 test_10 test_2 test_3 test_9 Wanghan

#passwd命令: Set User password

Administrator to modify their own password:

[Email protected]_168_102_centos ~fornew  Password:passwd:all Authentication tokens updated successfully.

The administrator modifies the other user's password:

[Email protected]_168_102_centos ~fornew  Password:passwd:all Authentication tokens updated successfully.

User to modify their own password:

for For Wanghan. (  Current) UNIX password:    // Enter present password new password:           new  password : Passwd:all authentication tokens updated successfully.

Passwd–l: Lock user Password, user cannot change password

[[Email Protected]_168_102_centos ~]# passwd-for  Wanghan. ( Current) UNIX Password:passwd:Authentication token manipulation Error

Passwd–u: Unlock user password

[[Email Protected]_168_102_centos ~]# passwd-for  Wanghan. ( Current) UNIX password:new password:

Passwd–s: Display user Password summary information

[Email protected]_168_102_centos ~]# passwd-2014-08-12 0 99999 7-1 (Password set, SHA512 crypt.)

#usermod命令: Used to modify the settings of the user account

Usermod–u UID: Modify user UID

[[Email Protected]_168_102_centos ~]# ID openstackuid=892 (OpenStack) gid=892 (OpenStack) groups=892  ~]# usermod-u 588~]# ID openstackuid=588 (OpenStack) gid=892 (OpenStack) groups=892 (OpenStack)

Usermod–g GID: Modifying user gid

[[Email Protected]_168_102_centos ~]# ID wanghanuid=500 (Wanghan) gid=2000 (Wudi)groups=2000 ~]# USERMOD-G 2001~]# ID wanghanuid=500 (Wanghan) gid=2001 (HP) groups=2001 (HP)

Usermod–g GID: Modifies the user-attached group, overwriting the original additional group by default, while using the-a option to add additional

[Email protected]_168_102_centos ~]# ID user1uid=899 (user1) gid=899 (user1) groups=899 (user1),  ~]# usermod-g 2001~]# ID user1uid=899 (user1) gid=899 (user1) groups=899 (User1), 2001~]# Usermod-a-Gto]# ID user1uid=899 (user1) gid=899 (user1) groups=899 (user1), (Wudi), 2001 (HP)

Usermod–c: Modify user account note information

[Email protected]_168_102_centos ~]# useradd-~]# tail-n 1/etc/passwduser2:x:900:900:hello:/home/ user2:/bin/~]# usermod-~]# tail-n 1/etc/passwduser2:x:900:900:test:/home/user2:/bin/ Bash

Usermod-d: Modify the user home directory, the home directory is not migrated by default, while using-M can be migrated

[Email protected]_168_102_centos ~]# usermod-d/tmp/Wanghan user1 [[Email Protected]_168_102_centos~]# tail/etc/passwdtest_2:x:889:500::/home/test_2:/bin/bashtest_3:x:890:890::/home/test_3:/bin/bashtest_4:x:891:891::/home/abc:/bin/bashopenstack:x:588:892::/home/openstack:/bin/bashtest_6:x:893:893::/home/qidian:/bin/bashwanghan11:x:894:894::/tmp/wanghan:/bin/bashtest_7:x:895:895::/home/test_7:/bin/bashtest_10:x:898:898::/home/test_10:/bin/tcshuser1:x:899:899::/tmp/wanghan:/bin/bashuser2:x:900:900:test:/home/user2:/bin/Bash[[email Protected]_168_102_centos~]# usermod-d/tmp/user2/-m User2[[email Protected]_168_102_centos~]# tail/etc/passwdtest_2:x:889:500::/home/test_2:/bin/bashtest_3:x:890:890::/home/test_3:/bin/bashtest_4:x:891:891::/home/abc:/bin/bashopenstack:x:588:892::/home/openstack:/bin/bashtest_6:x:893:893::/home/qidian:/bin/bashwanghan11:x:894:894::/tmp/wanghan:/bin/bashtest_7:x:895:895::/home/test_7:/bin/bashtest_10:x:898:898::/home/test_10:/bin/tcshuser1:x:899:899::/tmp/wanghan:/bin/bashuser2:x:900:900:test:/tmp/user2/:/bin/bash

Usermod–s: Modifying the user shell