1. What is a network? What is a computer network?
1) The network is composed of nodes and connections, representing many objects and their mutual relationships (Nima, what is this concept, I don’t understand it!)
2) Computer network refers to the connection of multiple computers and their external devices with different geographical locations and independent functions through communication lines, under the management and coordination of network operating systems, network management software and network communication protocols, A computer system that realizes resource sharing and information transfer.
These concepts, rote memorization may really not be important, I recommend the learning method in the movie "Three Silly Bollywood": What is a machine? The zipper on jeans is a machine. Some tools that help people save energy, including human inventions and creations, are all machines, and clocks are machines. The original text is as follows:
We are all working towards this direction!
Definition of book:
A method of recording, analyzing, organizing, summarizing, discussing, and interpreting information, illustrated or unillustrated, hardcopy or paperback, with or without cover, including a preface, introduction, table of contents, index, with A device that increases knowledge, deepens understanding, elevates and educates the human brain, using visual, and sometimes touch, sensory forms.
Find it in the lines to define yourself mechanically.
Professor: What are you laughing at?
Lancher: Teacher, studying engineering has been my dream since I was a child. I am very happy to be here.
Professor: Don't have fun, define a mechanism.
Rancher: The thing that saves you the effort is the mechanism.
Professor: Can you be more specific?
Lancher: Mechanisms make work easier and save time.
It's hot today, flip the switch, get gusts of cool breeze, the fan. Just a mechanical device.
Talk to friends thousands of miles away, phone calls, mechanical devices!
A quick calculation, a calculator, is a mechanical device!
A lot of mechanical devices around us, from pen heads to pants zippers, are mechanical devices. Up and down quickly.
Professor (throws a piece of chalk): What is the definition? ! !
Lancher: I just said that, teacher.
Professor: Do you do the same for exams? The mechanism is, up and down? idiot!
Anyone else speaking?
Chatur (the real idiot): Teacher, a mechanism is a combination of physical components, each part having a definite relative motion, whereby energy and momentum are converted into each other, like a screw and a nut, or a lever turning around a fulcrum, and also Hubs with pulleys, etc. In particular, the structure is somewhat complicated. Including the composition of moving parts, or simple mechanical parts such as rollers, levers, cams, etc.
Professor: Great! great!
Lancher: But teacher, I expressed the same meaning in simple language.
Professor: If you like simple expressions, go to the College of Arts and Crafts!
Lancher: But teacher, we have to understand what it means. Can't be a rote nerd.
Professor: Do you think you are smarter than textbooks? Write the definition in the book, sir, if you want to pass.
Lancher: But there are other books!
Professor: Get out.
(Halfway, Lancher walks back)
Professor: Why are you back?
Lancher: Forgot to order something.
Professor: What?
Lancher: A tool for recording, analyzing, summarizing, organizing. Discuss and explain knowledge. Pictured and Unpictured, Hardcover, Softbound, Sheathed, Unsheathed, With Foreword, Introduction, Table of Contents, Index, For Inspiration, Understanding, Improvement, Strengthening and Education of the Human Brain, Via Visual realization, and sometimes touch.
Professor: What do you want to say?
Lancher: Book, teacher. I forgot my book, can I get it?
Professor: Why don't you keep it simple?
Lancher: I tried it before, teacher, and it didn't work.
3) Use the network to achieve the following advantages!
a, share various resources on the network, files, pictures, small movies, scanners, printers and other services;
b. Data processing, such as scientific computing network, enterprise network;
c. Data transmission network, a network used to collect, exchange, and transmit data
2. Classification of networks
1) Local area network (LAN), an independent broadcast domain, such as each home; or LAN1, LAN2, LAN3 under each wireless router, independent local area networks;
2) Metropolitan Area Network (MAN): The scale is limited to a city; the concept is basically useless!
3) Wide Area Network (WAN): The network spans national borders, continental borders, and even the world, but the WAN port on the router can also be understood as a wide area network;
3. Transmission medium
1) Wired network - coaxial cable and twisted pair
2) Optical fiber network
3) Wireless network
4. Communication across local area networks
5. Make network cables
1) Twisted pair
2) Network cable pliers
3) Crystal head
4) T568A line sequence and T568B line sequence
5) Crossover cable and straight through cable
6. Classification of IP addresses
1) Public IP
2) Private IP
7. Common DOS commands
1）arp -a
2）ipconfig /all
3) ping www.jd.com -t #ICMP protocol
4) Directory structure of Windows
- C drive
- D drive
- E drive
Directory structure: C:\Windows\System32 The concept of absolute path and relative path;
5) dir, cd, .. and ., \, dirs, md folder name, rd folder name
02 python full stack s3 day3 why learn linux
As a developer, you must understand Linux;
1. Common operating systems: Windows, Linux, UNIX, MacOS;
2. The server is essentially a computer, serving multiple people;
3. The essence of the process of surfing the Internet is a process of downloading resources; for example, when visiting Tencent Video's website, video resources are stored on the hard disk of Tencent's servers. For example, the uploader's video on the notebook, everyone to share and watch, then the notebook is the role of a server;
4. The computer of the Windows system is basically turned on for a period of time, and a blue screen appears, and it needs to be restarted, but the restart will bring a bad user experience to the user, but the computer of the Linux system is very stable, and it does not need to be restarted for several years of continuous operation;
5. After the Web development is completed, the program needs to run on the server, and the Linux operating system is the first choice. It can be seen that the importance of Linux is self-evident.
03 python full stack s3 day3 course content introduction
1. Linux operating system and initial configuration (familiar);
2. Linux operating system directory structure and file-level addition, deletion, modification, and inspection operations (key points);
3. Linux operating system user and authority management (key);
4. Management of open source software and software packages under Linux (emphasis);
5, Linux operating system network foundation (emphasis);
6. Linux operating system status monitoring command (understand);
7. Linux operating system process management (key);
8. Network service foundation (understanding);
04 python full stack s3 day3 operating system kernel and system calls
1. Introduction to computer operating systems;
1) Operating system definition;
2) Master the definition of operating system kernel
- operating system kernel
- system call interface
- User Mode and Kernel Mode
3) Understand two operating system user interfaces: graphical interface and command line interface;
2. Understand the main Linux distributions: CentOS, RHEL, Fedora, Ubuntu, Suse
3. Preparations for installing the operating system
1) Understand why choose RHEL (RedHat Enterprise Linux) or CentOS
4. Install the Linux operating system;
05 python full stack s3 day3 operating system installation principle
1. The introduction of virtual machine concept - the use of VMware WorkStations14;
For the detailed operation process of installing CentOS7 on VMware WorkStation, see the following URI:
http://www.cnblogs.com/lynn-li/p/6077944.html
http://linux.it.net.cn/CentOS/server/set/2014/1230/11119.html
2. The concept of operating system image file (.iso file)
CentOS version image file download address (Aliyun): https://mirrors.aliyun.com/centos/
For example, the download link of CentOS7.4: https://mirrors.aliyun.com/centos/7.4.1708/isos/x86_64/CentOS-7-x86_64-Everything-1708.iso
06 python full stack s3 day3 linux operating system installation part1
1. Prepare the virtual machine to install the operating system;
- VMware WorkStation software;
- CentOS7.x image file;
- The process of creating a virtual machine (equivalent to going to Jingdong to buy a laptop without an operating system);
- In the host's BIOS, enable the CPU to support virtualization;
The following is the CentOS6.x installation tutorial, but I recommend using CentOS7.x, because our company's production environment is already the CentOS7 series, which is very stable and has many new features;
https://jingyan.baidu.com/article/1e5468f978d376484961b7be.html
07 python full stack s3 day3 linux operating system installation part2
1. After the installation is complete, click Reboot;
2. Different manufacturers' motherboards have different ways to enter the BIOS; there are common shortcut keys such as F2, F12, Del, and F1;
3. In the production environment, the graphical interface is not used, and the remote connection is made through the SSH tool;
- Xshell
- SecureCRT
- Putty
附注：现在基本已经步入“云计算”时代，更多公司优先选择将生产业务不熟在诸如，阿里云、亚马逊、Azure（微软）、腾讯云、百度云、金山云、京东云等云计算平台上，本人更倾向于使用——阿里云，俗话说：上云，就上阿里云！阿里云是中国的骄傲。
08 python全栈s3 day3 初识linux命令
1、CentOS官网www.centos.org；
2、UNIX和Linux操作系统概述
1）UNIX的定义
2）了解UNIX操作系统的特点：多用户和多任务
3）GUN项目与自由软件运动
4）Linux简介
5）登录和退出Linux
6）常见Linux操作命令
- ls
- cd
- mkdir
- rmdir
- whoami
- who
- date
- cal
- hwclock
- useradd、passwd
- userdel
详情见个人博客——linux命令大词典
http://www.cnblogs.com/tqtl911/p/8620527.html
7）LInux命令的格式
命令 【选项】 【格式】#中间至少一个空格分隔；
8）tty1~6终端与pts/0终端
9）Linux下快捷键的使用
- Ctrl+a、e、s、d、u、l、q、z
10）su与su - （switch user）的区别
11）最重要的，查看命令的帮助信息——man（推荐使用）、info、--help
3、小结
1）掌握Linux在VMwareWorkStation下的安装过程；
2）Linux操作系统的发展历程
3）GNU以及GPL协议、自由软件运动
4）Linux的常见操作命令；
- 1）init 0
- 2）exit
- 3）ls
- 4）whoami、who
- 5）date、cal
- 6）useradd、passwd
- 7）man --help
- 8）su与su -
附注：1、CentOS设置启动内存过低，将进入文本化安装界面；
09 python全栈s3 day3 linux操作系统目录结构
1、Linux系统的树形结构
1）Linux系统与Windows系统目录结构的区别；
2） 掌握决定路径和相对路径的概念；
10 python全栈s3 day3 目录及文件操作
1、目录文件的浏览、管理及维护
1）pwd ；mkdir;rmdir;
2）cd -；cd ~ ;cd ;cd ..;cd . ;cd /usr/local
3) cp
4)mv
5)Linux一切皆文件的思想；
6）环境变量与别名的概念；
7)cat;tac;more;less;head;tail;