Add sudo-related commands

en/linux/sudo.md

@@ -0,0 +1,33 @@
+# Running commands as superuser
+
+## Installing
+
+### Debian
+
+    apt-get install sudo
+
+## Sudoers Configuration
+
+    visudo
+
+Examples:
+
+    # User privilege specification
+    root    ALL=(ALL:ALL) ALL
+
+    username ALL=(ALL:ALL) NOPASSWD: ALL
+
+    # Allow members of group sudo to execute any command
+    %sudo   ALL=(ALL:ALL) ALL
+
+With this example, root can run all commands in any host and for any user using sudo.
+
+The user 'username' can do the same and doesn't need to type any password for that.
+
+All users in 'sudo' group can run any command as any user after typing their password.
+
+## Usage Example
+
+    sudo apt-get update
+    sudo apt-get upgrade
+    sudo -u postgres psql -l