How to Add/Remove FTP users in Linux and set permissions (follow-up) __linux

In the article "How to Add/Remove FTP users and set permissions in Linux", we talked about how to add and remove users, but later, we still encountered a lot of

Problem:

1. After entering the system, the command line has only a dollar sign such as "$", and the environment variable file is already copied to the user's home directory, how to revert to the xxx@ host name: ~$

Such a format.

vim/etc/passwd

See your own user name, such as:

TEST:X: ():()::/home/test:

Add/bin/bash to the back and you'll be fine.
That

TEST:X: ():()::/home/test:/bin/bash

If the "/etc/passwd" E212:can ' t open file for writing appears, there is a problem with the permissions, and after exiting, the Chattr-i/etc/passwd is executed and can be changed.

2. Unable to use root permissions

test@iz28m0c0sk6z:~$ sudo-i
[sudo] password for test: The ' isn't in ' 
sudoers file.  This incident would be reported.

(1) Add Write permission to the sudo file, the command is:

chmod u+w/etc/sudoers

(2) Edit sudoers file

Vim/etc/sudoers

Find this line

Root all= (All:all) all

Add below it:

XXX all= (all:all) all #这里的xxx是你的用户名

PS: Here you can sudoers add any of the following four lines.

Youuser            all= (All)                all
%youuser           all=-                all Youuser all=
%youuser           All= (All)                Nopasswd:all

First line: Allows the user to Youuser execute the sudo command (requires a password).
Second line: Allows users in the user group Youuser to execute sudo commands (require a password).
Third line: Allows the user to execute the sudo command youuser, and does not enter the password at execution time.
Line four: Allows the user group Youuser users to execute sudo commands and not enter the password at execution time.

(3) Revoke sudoers file Write permission, command:

chmod u-w/etc/sudoers

This allows the average user to use sudo.