0、 Write it at the front （ This content has nothing to do with the task , Only when I write code, I find that I need to use it many times sudo, So I wrote to use sudo You don't have to enter a password every time. Solution ）：

	1. Open file 
			sudo vim /etc/sudoers
	2. modify /etc/sudoers The last line of the document 
			 take 
			%sudo   ALL=(ALL:ALL) ALL   
			 It is amended as follows   
			%sudo   ALL=(ALL:ALL) NOPASSWD:ALL

1、 Brief introduction to the task ：

Raspberry Pi（ Chinese name “ Raspberry pie ”）, It's a microcomputer the size of a credit card , Its system is based on Linux. In order to improve the Internet environment of the school dormitory （ The campus network login system leads to the inability to use the router multi device general network ）, Visit the campus network through raspberry pie, log in to the system, and 24 Hour boot sharing hotspot to achieve 24 More than hours of device Internet access .

2、 adopt mentohust Log in to the wired end of Ruijie campus network , And implement mentohust Boot from boot

stay linux Using campus network under the environment of , Like Ruijie's classmates , It's still a headache for surfing the Internet . Ruijie's own linux It seems that the client has not been updated for a long time , It doesn't work very well . We recommend you to use the... Developed by Huazhong University of science and technology mentohust, Good online reputation , Bloggers can use it after testing and configuring it , Here is a brief introduction mentohust Installation and use .

1. download mentohust file , Here is the use of git clone Command download ;

   		sudo git clone https://github.com/hyrathb/mentohust
   

2. After downloading, enter mentohust Folder , And install ;

   1. Get into mentohust Folder 
   		cd mentohust 
   2. The following libraries are necessary to run , It is recommended to install one by one 
   		sudo apt-get install build-essential
   		sudo apt-get install autopoint
   		sudo apt-get install automake
   		sudo apt-get install autoconf
   		sudo apt-get install gettext-base gettext liblocale-gettext-perl
   3. next 
   		sh autogen.sh
   4. Then configure 
   		./configure --prefix=/usr
   		sudo make
   		sudo make install  Compilation and installation 
   		sudo chmod u+s /usr/bin/mentohust
   5. Then install and run mentohust Required libraries 
   		sudo apt-get install libpcap-dev libnotify-dev
   		sudo mentohust
   6. Set the corresponding parameters :
   		1. Select the corresponding network card   user name   password 
   		2. Multicast address (multicast address) choice  1 Agility 
   		3.dhcp The way (dhcp type) choice  3 Before certification 
   7. Not surprisingly, you can see the authentication options , Fill in the account number and password , Should be able to connect to the campus network 
   

3. Set power on self start , So you don't have to run every time you start up sudo mentohust The command , I used it here apt-get install sysv-rc-conf To manage startup items ;

   1.# Installation method ：
   		sudo apt-get install sysv-rc-conf 
   2.cd To /etc/init.d Under the table of contents , Use root Permission to write scripts ：login.sh
   		cd /etc/init.d
   		sudo vim login.sh   #( If not installed vim Students can search and install vim And learn vim How to use )
   3. Write the following script ：
   		#!/bin/bash
   		sudo mentohust<<" Here is your root Account password "
   4. Change the permissions of the script file to daemon ：
   		chmod +x login.sh
   5. use sysv-rc-conf Command to set the running level of the daemon 
   		sysv-rc-conf login.sh on
   4. preservation login.sh File and exit , After restarting, you can find that you can automatically log in to the campus network .
   		sudo reboot
   

   PS： This method can be applied to the startup items set by many users

3、 Raspberry pie install hotspot sharing program create_ap, And realize automatic startup

1. create_ap Install and open the raspberry pie hotspot

   1. Put the code clone To local 
   		sudo git clone https://github.com/oblique/create_ap
   		cd create_ap
   		sudo make install
   2. Install dependent Libraries 
   		sudo apt-get install util-linux procps hostapd iproute2 iw haveged dnsmasq
   3. Turn on the hotspots 
   		sudo create_ap --no-virt wlan0 eth0  Hotspot name   Hot code 
   

2. take create_ap Start as a service , The raspberry pie hot spot can be started automatically

   1. Modify service configuration , add to --no-virt Parameters 
   		sudo vim /usr/lib/systemd/system/create_ap.service
   		#  take create_ap.service Medium 
   		ExecStart=/usr/bin/create_ap --config /etc/create_ap.conf
   		#  It is amended as follows  
   		ExecStart=/usr/bin/create_ap --no-virt --config /etc/create_ap.conf
   	
   2. Default profile /etc/create_ap.conf, Change the following two horizontal lines to your own ssid And password , Modify your own dhcp gateway 
   		sudo vi /etc/create_ap.conf
   		# take create_ap.conf In the document 
   		GATEWAY=10.0.0.1
   		SSID=MyAccessPoint
   		PASSPHRASE=12345678 
   		#　 It is amended as follows 
   		GATEWAY=192.168.123.1
   		SSID= The hotspot name you want to set 
   		PASSPHRASE= The hotspot password you want to set 
   3. About the service startup code （ Only the last three lines need to be used to set the boot auto start ）：
   		#  Start a service ：
   		systemctl start create_ap.service
   		#  Shut down a service ：
   		systemctl stop create_ap.service
   		#  Restart a service ：
   		systemctl restart create_ap.service
   		#  Show the status of a service ：
   		systemctl status create_ap.service
   		#  Enable a service at boot time ：
   		systemctl enable create_ap.service
   		#  Disable a service at boot time ：
   		systemctl disable create_ap.service
   		#  Check whether the service is started ：
   		systemctl is-enabled create_ap.service