Study NOTE _ linux-linux basics

Unix is secure, reliable, powerful, and has multiple users. Linux free version before Unix installation knowledge preparation hard disk and partition primary partition installation operating system

Unix is secure, reliable, powerful, and has multiple users.
Linux free version of Unix

Prerequisites
Hard disk and partition
Install the operating system in the primary partition
Extended partition data storage
Logical Partition

Everything is a file
Hard disk
IDE -- hdx (x is abcd ...)
SCSI -- sdX (X is ABCD ...)
Partition
Hard disk file name + partition number
For example, the first partition in the first IDE hard disk is hda1.
The fourth partition of the second SCSI hard disk: sdb4
Linux has only four primary partitions and four extended partitions, ranging from 1 to 4.
Logical Partition: starting from 5
Up to 63 Ides
SCSI to 15
File system
Windows: Common File Systems: FAT32, NTFS
Linux: EXT3 is compatible with EXT2 and has the file system logging function.
It is easy to quickly return to the normal state when the power is down
Features:
1. high availability does not require detection of the file system, making it easy to recover abnormally
2. avoid file damage due to abnormal shutdown due to data integrity
3. file system speed
High Scalability of EXT4
SWAP is used for data exchange between memory and hard disk, and virtual memory
About twice the physical memory

Directory structure
In linux, add all files to a tree directory and use/to indicate classification.
/Root directory
/Root-level Directory
/Bin
/Root/Desktop level 2 Directory
.
.
Common subdirectories and their functions
/Boot files required to start linux
/Bin basic user commands
/Dev device file (hard disk, keyboard)
/Etc configuration file
/Home user's default working directory
/Root user's working directory
/Sbin basic management commands
/Usr user application
/Var files that frequently change
/Tmp temporary file

Red Hat Linux
Installation 1. Machine installation
2. dual-system coexistence installation
3. Virtual Machine installation
Boot 1. CD boot
2. USB device boot
Read software package 1, CD
2. hard disk
3. Network Server

Windows virtual machine linux installation
1. install virtual machines
Install vmwarevm software
Create a VM
Operating system type: Linux
Memory is set to 1 GB +
Hard Disk 4 GB +
Configure virtual machines
2. install Red Hat

Basic operations
Graphic interface operation
Document Editor
Text Edtor file editor

Character interface operations
Linux features, saving network transmission memory
1. use console shortcut keys
2. log on to the linux host using remote logon
3. use the pseudo character terminal in the graphic interface
Quick console
Six virtual terminal tty1-tty6 by default
Press Ctrl + Alt + Fn to switch to the corresponding Virtual Terminal
Alt + F7 back to the interface
Add shift in the graphic interface
Remote
SSH tools
Pseudo character Terminal