Some useful commands

sudo & gksudo (for GUI sudo)

 

Stop XWindows

sudo /etc/init.d/gdm stop

keyboard shortcut:

via SSH from Linux (user "live"): # ssh live@192.168.2.4

via SSH from Windows: ssh-client "Putty" (for example)

 

add a user

MIn user (guest)  useradd -u 501 -m -s /bin/bash -g users looser1

Max user (admin)  useradd -u 999 -m -s /bin/bash -g users looser1

In the terminal this would be: sudo adduser $user admin, where you replace $user with the name of the user.

if you want to avoid typing SUDO for each command then use:   sudo -i

 

important files

/etc/apt/sources.list           <<< this contains the server catalogue for possible update or new application

 

 

Links

 

http://www.linux.com/articles/54945

 

 

 

 

How to set/change/enable root user password

sudo passwd root

How to disable root user account

sudo passwd -l root

How to allow root user to login into GNOME

System -> Administration -> Login Window

Login Windows Preferences

Security Tab -> Security -> Allow local system administrator login (Checked)

How to switch to root user in Console mode

sudo -s -H
Password: <specify user password>

or

sudo su
Password: <specify user password>

How to add/edit/delete system users

System -> Administration -> Users and Groups

Users and Groups

Users Tab -> Add User…/Properties/Delete

or

sudo useradd matt
sudo userdel matt

How to add/edit/delete system groups

System -> Administration -> Users and Groups

Users and Groups

Groups Tab -> Add Group…/Properties/Delete

How to automatic login into GNOME (not secure)

System -> Administration -> Login Window

Security Tab -> Enable Automatic Login (Checked)

Now choose a user from the drop-down menu.

How to allow more sudoers

sudo adduser a_username admin

How to change files/folders permissions

Right click on files/folders -> Properties

Permissions Tab -> Read/Write/Execute (Checked the permissions for Owner/Group/Others)

How to change files/folders ownership

sudo chown system_username /location_of_files_or_folders

If you want to change ownership of all containing files and folders recursively, use the -R option like this:

sudo chown -R system_username /location_of_files_or_folders

How to change files/folders group ownership

sudo chgrp system_groupname /location_of_files_or_folders

If you want to change group ownership of all containing files and folders recursively, use the -R option like this:

sudo chgrp -R system_username /location_of_files_or_folders