1、
log in
[root@localhost] root
password 123 (the default seems to be 123456)
User rights
The root authority is the highest, equivalent to the administrator in Windows
In the Linux system, the user authority is distinguished by UID, UID = 0, which means that the user has the highest authority
2. Basic commands
cd command: switch directory
cd / switch to the root directory
cd .. return to the previous directory (relative to the current directory, this path is also a relative path)
cd. Return to the current directory
cd tmp switch to tmp directory (switch absolute path)
pwd command:
pwd view the current directory location
ls command:
ls view all folders in the root directory
clear command: clear screen
mkdir command: create directory
mkdir directory name creates an empty directory
mkdir -p directory name / directory name (directory file) Create a parent-child directory and a directory (or file) under the directory at the same time
mkdir -v directory name creates an empty directory and displays the successful creation information
mkdir -vp directory name / directory name (directory file)
Example:
mkdir creates a directory:
rmdir command:
rmdir directory name (only directory can be deleted-empty directory)
rmdir -p directory name / sub directory name (if the sub directory is deleted, the parent directory is empty, then delete it together)
rm command: used to delete a directory and all directories and files under this directory
rm file name (not forced to delete, need to delete confirmation)
rm -f file name (force delete file, no need to confirm)
rm -r directory name (delete a directory and all directories and files under this directory, need to confirm)
rm -rf directory name (force to delete a directory and all directories and files under this directory)
rm -i * .xxx (delete the file with the suffix xxx)
cp command: used to copy files or directories
mv command: move or modify a file name (directory)
mv file name 1 directory name / file name 2 (if file 2 exists, file 1 asks whether to overwrite file 2; if it does not exist, file 1 name is changed to file 2, or file 1 moves to this directory)
mv file name 1 -b directory name (the backup file is the file to be overwritten by file name 1 under the path behind -b)
touch command: create file
touch file name
touch file name file name 2 file name 3 (create multiple files at the same time separated by spaces)
vi command: can write text content
vi file name
After you press Enter to enter, you will enter the editing interface. Enter i to edit the content. After editing, click the esc button to exit the editing. Press shift +: enter wq at the bottom of the input interface to save the edit and exit.
cat command: you can view the contents of the file
cat file name
Example:
echo command: You can directly print out the content, or you can directly modify the content of the file
echo “xxxxxx” will directly output xxxxxx after pressing Enter
echo xxxxxx> The file name will directly replace the file content with xxxxxx
echo xxxxxx >> The file name will append xxxxxx after the file content
Example:
3. Learning skills
Practice to know, practice more-practice more-practice more
4. Make up for problems in installing Linux
During installation, when selecting Chinese, the Linux installation interface of the Rad Hat version shifted to the right and there was no complete display
Red Hat Enterprise Linux (slow start? Maybe it's my computer)
CentOS version of Linux (normal boot speed)
During installation, disk partitions need to be divided
At least two disk partitions:
Root partition:
Mount point: /
File type: ext4
Swap partition:
Mount point: None
File system type: swap
Size: twice the physical memory
There is another way to divide the disk, which is to follow the installation prompt directly.