12.1 Types of User
12.1.1 System Default Users and Additional Created Users
12.1.1.1 System Default User
In Raspberry Pi, there are users which are provided by default when the system is installed, and those are “pi” and “root” user account. The “pi” user account is the default user provided for system administration, and the “root” user account is the super-user account with all the privileges required for system administration.
Chapter 12 User and User Group
Chapter’s Main Topics
This chapter describes the various kinds of user accounts and explains the difference between logon user and working user. It also describes how to create user account, change the contents of user account, delete user account, and describes the relationship between user account and user group.
It includes descriptions on the following topics:
■ Types of user
■ Logon user and working user
■ Internal management of user account in the system
■ Create, change, or delete user accounts
■ User groups
11.8.2 Registering & Releasing Bluetooth Devices to Raspberry Pi
When you connect Raspberry Pi to an external device, you can start the device connection request from Raspberry Pi or from an external Bluetooth device. Depending on who initiates the connection request, the process is slightly different.
11.8 Configuration and Connection of Bluetooth
The Raspberry Pi 3 model B provides Bluetooth functionality as standard. Therefore, without purchasing a separate device, you can easily connect to various devices supporting Bluetooth around Raspberry Pi, such as mobile devices, and do an interesting works easily.
To configure Bluetooth settings, you can use the Bluetooth menu in the [Tools] area of the Desktop window.
11.7.2 Activation and Stop with “ifconfig” Command
We used the “ifconfig” command to look up the current state of the network. However, this “ifconfig” command can also be used to activate or stop the network using “up” or “down” as an option.
The command format used to activate the network device is as follows
11.7 Activation and Stop of Network
While operating the system, you may need to stop and reactivate the network device as needed for various reasons, such as an error occuring or changes to the configuration. If the existing device is stopped, the network connection is disconnected, and the IP address that was previously assigned can not be used. When the connection is stopped and a new connection is made, the network connection is made according to the latest setting contents.
You can use several commands to stop and reactivate the Raspberry Pi system. Let’s look at each command one by one.
11.7.1 Network Activation/Stop by “ifup” and “ifdwon” Command
11.6.2 How to Set up Static IP Address in Raspberry Pi
The default setting for the IP address in the Raspberry Pi system is stored in “/etc/network/interfaces” file. Normally, the contents as follows are stored.
iface lo inet lookback
iface eth0 inet dhcp
iface wlan0 inet dhcp
wpa-ssid “wifissid”
wpa-psk “wifipassword”
11.6 Setting Static IP Address
Normally, when connecting a computer to a network, it is general that the computer is automatically assigned the IP address from the DHCP server, but the IP address for each computer can be fixed as needed. As a method for fixing IP address for a specific computer, there are method of assigning the IP address by setting “manual IP allocation” in the DHCP server and method of assigning the IP address in the individual computer.
11.6.1 How to Specify Static IP Address on DHCP Server
In a typical small network, such as a home or small office, the network is configured so that a router acts as a DHCP server. In this method, a DHCP server may specifies a fixed IP address predefined for a specific computer. Then, when the computer connects to the network, it is assigned the predefined fixed IP address. At this time, you usually use the Mac address assigned to the computer hardware to distinguish a specific computer.
11.5.2 Setting Wireless Connection with Configuration File
The default settings for the network in the Raspberry Pi system are stored in the file “/etc/network/interfaces”. In this file, you can activate the wireless connection by directly entering the settings for the wireless connection.
If you have already configured with the window Wi-Fi configuration tool, it will have the following contents, and you will need to delete all this contents.
11.5 Wireless Connection
Starting with the Raspberry Pi 3 model, Wi-Fi devices are installed by default. So you can use Wi-Fi without buying a separate device. However, to use Wi-Fi on previous Raspberry Pi models, you must purchase and install a separate USB Wi-Fi device.
To connect to the network wirelessly via Wi-Fi, you need to connect to a wireless access point, which requires Wi-Fi settings to connect wirelessly. The window in the Raspbian distribution includes a tool to simplify Wi-Fi configuration.
11.5.1 Setting Wi-Fi with Panel Menu
This section describes the settings of Wi-Fi that are installed by default from the Raspberry Pi 3 model.