Assignment 1.0: File Permissions & User Groups

Commands

Cheat Sheet

Steps to create user and add to group

1. useradd example_user = will add user of selected name

2. passwd example_user = makes it so you can create password for user

3. groupadd example_group = will create the new group

4. usermod -aG example_group example_user = this will add user to a selected group

5. su - example_user = will become that user

6. chgrp example_group /example_directory = will apply the example_group to the example_directory

7. chmod = will allow you to change permission for file/directory

   • chmod g+rwx /example_directory or file = will allow the group permission to read, write, and execute

   • chomd g-rwx /example_directory or file = will get rid of the ability to read, write, and execute for the group permissions

   • g = is for group

   • o = is for other

   • chomd g-rwx * = all files in current directory will be effected

   • chomd -v num example_file = will change permissions using binary to decimal

     • num is decimal number like '600' = for this the owner gets r and w (r+w = 6) and 0 means no permissions for the other sections

     • read = 100 (binary) = 4

     • write = 010 (binary) = 2

     • execute = 001 (binary) = 1

8. id = shows what groups and uid for logged in user

9. echo text >> /example_directory/example.txt = will append text to example.txt

10. echo text > /example_directory/example.txt = will over write text to example.txt and or create file example.txt with text in it

Side notes

1. chown example_user example_file = Will change the owner of the file to specified owner

List commands

1. ls = shows directories in current directory

   • ls -l /example = will show all the files in directory * drwxr-xr-- owner group file/directory name * drwxrw-r-- owner group file/directory name * drwx-wxrw- owner group file/directory name

   • ls -ld /example = listing directory instead of at the file level * example: drwx------ owner group directory name

2. drwxrwxrwx = who can read write and exicute

   • first 4 are the owner

   • next 3 are the group

   • last 3 are what others can do

   • drwx------ owner group file/directory name

     • only the owner would be able to see read write and exicute this file/directory