(1) from the user to switch the user to root
Whether Login Ubuntu, or log in command line mode graphics mode, we will find the default user is the user
But when we need to do something (such as a file system repair also) have root privileges, often need to use sudo authorization, I feel a lot of trouble
At this point we can switch to the root user, simply executing sudo su to
Note: For security reasons, there is no fixed root user password Ubuntu's default, which password is randomly generated and dynamically change
, It looks like a change every five minutes, so use su (switch user) is not possible, because we do not know the root password
(2) user user switch back from the root user
Want to cut back from the root user user user simply execute the command: su user (user installation time is your own user name), or enter exit, also launched key combination Ctrl + D
(3) setting a password to the root
The default root user password is not fixed, and is locked, if you want to set a root password
Just execute the command: sudo passwd root and follow the prompts step by step
Such may provide both (1) inside the above mentioned su root switch, root password to the root user
Note: After setting the password to the root, you can still sudo su to root
Attached: in graphic mode System -> Administration -> users and groups can also be provided to the root password
(4) disable and enable root login
Execute sudo passwd -l root can (just disable the root, but the root password is still preserved), and then execute su root discovery authentication fails,
To start again root login, execute sudo passwd -u root can
(5) make Ubuntu auto-login
Graphics mode System -> Administration -> Login Window after authorization unlock selection
As a user can be automatically logged.
Vb enhancement on installing problems:
sudo APT-GET install the make
sudo APT-GET install Linux-headers - $ (uname -r)
if not enough, coupled with a sudo apt-get install build-essential and then reboot it.