Linux Study notes second lesson of the third week (February 6)

3.4 usermod Command

Change user Properties Usermod,

Change uid, command is #usermod-u number;

Change GID, command for #usermod-g number;

change The user home directory, the command is #usermod-d number;

change The user shell, the command is #usermod-s number;

Set the user expansion group, the command is #USERADD-G Group name ", group name";

View aming user Uid,gid, expansion group, #id aming;

Lock user cannot use, command for #usermod-l aming;

Unlock user, command for #usermod-u aming;

3.5 User Password Management

Modify the user password, the command is #passwd user name;

View user Password profile, command for the first 10 lines #head/etc/shadow or 10 lines #tail/etc/shadow;

Lock user cannot use, command is #passwd-l user name; password profile password bit plus two exclamation mark;

Modify the user password, clear text display password, command for #passwd--stdin User5;

Modify user password,#echo "111222" |passwd--stdin user5;

#echo-E implements some special usages, \ n newline character, \ t is tab, command is #echo-e "123\nsss";

Modify the user password, a command to enter the password two times, the command for #echo "1231111\n1231111" |passwd User3;

3.6 mkpasswd Command

Randomly generate a string as a password, command mkpasswd,make password;

installation Command MKPASSWD package #yum install-y expect;

Use method, command for #mkpasswd;

-l Specifies the length, the command is #mkpasswd-l number;

-S special symbol number, command for #mkpasswd-s number;

Linux Study notes second lesson of the third week (February 6)