This is the sixth day of my participation in the More text Challenge. For details, see more text Challenge

First, basic introduction

Version 1.

  • The server
    • RedHat
      • Centos: a free version of RedHat with fewer system management tools than RedHat
      • RedHat 7 —— centos 7
    • Suse
      • openSuse
      • Suse Enterprise
  • Personal PC
    • Ubantu

2. Linux directory structure

/root directory /bin Linux commands are also called shell /boot driver-related /dev device Device-related /home Stores user information /usr user resource Stores the software installed by the user /root root Super administrator folderCopy the code

3. “Line breaks”

  • Replace Windows newline with Linux newline in shell scripts under Linux:
    • sed -i 's/\r//' filename
    • The default value is in window\r\n
    • Under Linux is\n
    • Unix is\r

4. Three installation modes

  1. RPM tool: RPM -ivh [RPM complete package name] This tool is similar to the Offline installation package EXE in Windows
  2. Yum install -y [Package name for short] The python tool operates RPM packages
  3. The source code package:./confifure –> make –> make install (.Needs to be compiled into an executable file)

Linux and Unix

  • Unix commercial cores are not exposed to hardware and cannot be installed on X86 and PERSONAL computers
  • Linux free source code open free use of hardware requirements are relatively low
  • Centos is a free version of redhat recompiled and fixed, using the same source code
  • Redhat is a paid commercial version; Centos Free Trial

3. Common commands

Viewing the Kernel Version

cat /proc/version

uname -a

Check the memory

Free -m Displays the memory usage in MB

Check the hard disk

df -hl

Viewing Resource Consumption

top

  • M sorted by memory usage

Viewing Resource Information

cat /proc/cpuinfo

cat /proc/meminfo

df -h

Hard link, soft link

Java hello hard link ln -s hello. Java Hello soft link

To find the command

  • The which directive looks for files that match the criteria in the directory set by the environment variable $PATH.
  • File search
    • find / -name xxx*Find all files starting with XXX from/and directory by filename
    • find / -size 8kFind files by size
  • File content search
    • grep "aa" xx.txtSpecify file xx.txt to find the AA string

Compression and packing

  • The compression
    • tar -czvf my.tar.gz /etc
      • -z Calls the gzip command to compress
      • -C Packaging is common
      • -v Displays the processing process
      • -f Specifies the file name
  • packaging
    • tar -xvzf my.tar.gz
    • tar -xvzf my.tar.gz -C /tmp
      • -x: unpack;
      • -f: specifies the file name of the compressed package.
      • -v: displays the file packaging process.
      • -t: test, which is to check what files are in the package without packaging.
      • -c directory: specifies the unpacking location.