搭建樹莓派無線路由器

1. 採購硬件

• 樹莓派（去年買的Raspberry Pi 2 Model B 1GB 一直喫灰，不能忍）
• USB無線網卡(購買鏈接：http://item.jd.com/509932.html)，新版樹莓派3自帶無線模塊，應該無需購買
• 選用設備
  • 網線（方便調試）

2. 裝樹莓派官方系統，更新，基礎配置

• 略（不會配置，找個文檔看看）

3. 安裝 hostapd + udhcpd

apt-get install -y hostapd udhcpd

• udhcpd 配置

    root@raspberrypi:~# cat /etc/udhcpd.conf
    start 192.168.42.2 # This is the range of IPs that the hostspot will give to client devices.
    end 192.168.42.20
    interface wlan0 # The device uDHCP listens on.
    remaining yes
    #opt dns 8.8.8.8 4.2.2.2 # The DNS servers client devices will use.
    opt dns 223.5.5.5 223.6.6.6 # The DNS servers client devices will use.
    opt subnet 255.255.255.0
    opt router 192.168.42.1 # The Pi's IP address on wlan0 which we will set up shortly.
    opt lease 864000 # 10 day DHCP lease time in seconds
  

• hostapd 配置

  • 注意driver=rtl871xdrv 不是nl80211，因爲奶茶東的usb網卡硬件不一樣（rtl8192cu）
  • 替換/usr/sbin/hostapd這個二進制文件（外國友人鏈接：https://dl.dropboxusercontent.com/u/1663660/hostapd/hostapd）

  因爲硬件的適配性問題，默默調試了3-4h，各種搜（樹莓派3應該不存在這種問題）

    root@raspberrypi:~# lsusb |grep WLAN
    		Bus 001 Device 004: ID 0bda:8176 Realtek Semiconductor Corp. RTL8188CUS 802.11n WLAN Adapter
  
    root@raspberrypi:~# lshw -C network
    *-network:0
       description: Wireless interface
       physical id: 1
       bus info: usb@1:1.3
       logical name: wlan0
       serial: e8:4e:06:2a:5e:73
       capabilities: ethernet physical wireless
       configuration: broadcast=yes driver= rtl8192cu ip=192.168.42.1 multicast=yes wireless=IEEE 802.11bg
  

hostapd配置

	root@raspberrypi:~# cat /etc/hostapd/hostapd.conf
	interface=wlan0
	driver=rtl871xdrv
	ssid=行者孫
	hw_mode=g
	channel=6
	macaddr_acl=0
	auth_algs=1
	ignore_broadcast_ssid=0
	wpa=2
	wpa_passphrase=haha1234
	wpa_key_mgmt=WPA-PSK
	wpa_pairwise=TKIP
	rsn_pairwise=CCMP

4. 內核 iptable 網絡 配置 啓動項

• 內核

    root@raspberrypi:~# grep net.ipv4.ip_forward=1 /etc/sysctl.conf
    net.ipv4.ip_forward=1
  

• iptables

    root@raspberrypi:~# cat /etc/iptables.ipv4.nat
    # Generated by iptables-save v1.4.14 on Sat Apr 30 16:59:41 2016
    *filter
    :INPUT ACCEPT [23:1360]
    :FORWARD ACCEPT [0:0]
    :OUTPUT ACCEPT [21:3136]
    -A FORWARD -i eth0 -o wlan0 -m state --state RELATED,ESTABLISHED -j ACCEPT
    -A FORWARD -i wlan0 -o eth0 -j ACCEPT
    COMMIT
    # Completed on Sat Apr 30 16:59:41 2016
    # Generated by iptables-save v1.4.14 on Sat Apr 30 16:59:41 2016
    *nat
    :PREROUTING ACCEPT [2:156]
    :INPUT ACCEPT [2:156]
    :OUTPUT ACCEPT [1:108]
    :POSTROUTING ACCEPT [0:0]
    -A POSTROUTING -o eth0 -j MASQUERADE
    COMMIT
    # Completed on Sat Apr 30 16:59:41 2016
  

• 網絡配置

    root@raspberrypi:~# cat /etc/network/interfaces
    auto lo
    iface lo inet loopback
    iface eth0 inet dhcp
  
    auto eth0
    allow-hotplug eth0
  
    auto wlan0
    allow-hotplug wlan0
    iface wlan0 inet static
      address 192.168.42.1
      netmask 255.255.255.0
  
    pre-up iptables-restore < /etc/iptables.ipv4.nat
  

• 啓動項

    root@raspberrypi:~# history | grep enable
      103  update-rc.d udhcpd enable
      104  update-rc.d hostapd enable
  

4. 手機電腦連接測試，效果感人

測試速度很快。主觀自我肯定，客觀硬件配置的確秒殺絕大部分路由器

ssid：行者孫
password: haha1234

5. 總結

Hi, GNU/linux 陪伴是最長情的告白，等我財務自由了我賺錢給你！

• 消滅沒有女朋友的無聊的人山人海的五一假期
• 擁有一個自由控制的linux router
• 自我陶醉
• 物盡所用