Ubuntu 12.04 root Login settings and no solution to the sound problem after root login

1. In the terminal window input: sudo-s and then enter the normal user login password, enter can enter the root user rights mode.

2. Execution: sudo gedit/etc/lightdm/lightdm.conf #在打开的文件中增加如下内容

Greeter-show-manual-login=true #手工输入登陆系统的用户名和密码

Allow-guest=false #不允许guest登录

3. Execution: sudo passwd root to enter the root account password as prompted.

4. Restart Ubuntu, the login window will have "login" option, this time we can login through root.

Ubuntu under Root, the default is to shut down the sound system for security reasons.
If it's easy to drive, the PulseAudio does not start after root login. So you start it first.
Add root to the pulse and pulse-access groups:
sudo usermod-a-g pulse-access Root
Gpasswd-a Root Pulse
Gpasswd-a Root pulse-access
And then:
Edit/etc/default/pulseaudio File

cp-p/etc/default/pulseaudio/etc/default/pulseaudio.bak Vim/etc/default/pulseaudio
Modify the following two places
Pulseaudio_system_start=1

disallow_module_loading=0 to 1 and 0, which indicates that the system environment is allowed to run, allowing dynamic loading of modules.
Restart the computer, and the sound will come out.