Purpose of the this hands-on training is to teach the students how to manage users and groups.
At the end of the this hands-on training, students will be able to;
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explain users and groups in linux.
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manage users and groups.
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Part 1 - Basic User Commands
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Part 2 - User Management
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Part 3 - User Passwords
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Part 4 - Group Management
- whoami.
whoami
sudo su
pwd
whoami
su ec2-user
sudo su -
pwd
- who.
exit
who
who # open a new shell and retry who command to see the users who logged in.
- w.
w
who
- id.
id
id root
sudo su
useradd user1
id user1
- su.
su ec2-user
su user1
sudo su user1
pwd
exit
sudo su - user1
pwd
- passwd.
exit
sudo su
useradd user2
passwd user2 # give a password to user2
su - user2
passwd
exit
su user2
- /etc/passwd.
exit
cat /etc/passwd
tail -3 /etc/passwd
- useradd.
sudo useradd user3
cd /home
ls
cd /etc
ls login*
cat login.defs
sudo nano login.defs # change the CREATE_HOME variable's value to "no"
sudo useradd user4
cd /home && ls
cat /etc/passwd
sudo useradd -m user5 # force to system to create a home directory for user with -m option.
cd /home && ls
sudo useradd -m -d /home/user6home user6 # change the user's home directory name with -d option.
ls
sudo useradd -m -c "this guy is developer" user7 # give a descrpition to user with -c option.
cat /etc/passwd
cat /etc/passwd | grep user7
- userdel.
cat /etc/passwd
sudo userdel user5
cat /etc/passwd
cd /home && ls
sudo userdel -r user1 # delete user and its home directory with -r option.
cd /home && ls
- usermod.
cat /etc/passwd
sudo usermod -c "this guy will be an aws solution architect" user7
cat /etc/passwd
sudo usermod --help
sudo usermod -l Superuser user2 # change the name of the user2 with -l option.
cat /etc/passwd
- passwd-etc/shadow-etc/login.defs.
sudo su
useradd user8
passwd user8
cd /etc
cat shadow
cat login.defs
- groups.
groups
sudo groupadd linux
sudo groupadd aws
sudo groupadd python
cat /etc/group
groups
sudo usermod -a -G linux ec2-user # append ec2-user in linux group.
cat /etc/group
groups
sudo usermod -G aws ec2-user # this command deletes all groups that ec2-user in except default group of ec2-user and add ec2-user to aws group.
cat /etc/group
sudo groupmod -n my-linux linux # change the name of the linux group.
cat /etc/group
groups
cat /etc/group
sudo groupdel python
cat /etc/group
sudo gpasswd -a user7 aws # add a user to a group.
cat /etc/group
sudo gpasswd -d user7 aws # delete a user to a group.
cat /etc/group