Simple Linux Command learning notes, linux learning notes

Simple Linux Command learning notes, linux learning notes

1. View Processes

Ps-ef | grep keyword/* keyword is service name */

Netstat-unltp | grep keyword/* the keyword is the service name or port */

 

2. Killing Processes

Kill-9 process no./* exercise caution when performing operations */

 

 

3. view files by PAGE

Cat file name | less

Press enter,

Enter or press the next line.

[Top key] one line on the Internet

[Space key or PgDn] Flip down

[PgUp] Page up

[Q] exit to view

 

4. edit a file

Vi file name

[I] enters the editing status

[Esc] exit the editing status and can only be viewed

[: Q] exit the editing file and do not save it.

[: Q !] Force exit the edit file and do not save

[: Wq] Save and exit

[: Wq !] Force save and exit

 

5. Listen to files

Tail-f file name

[Ctrl + c] exit

 

6. View firewall policies

Iptables-L-n -- line-number/* display row number */

Iptables-L-n

Or cat/etc/sysconfig/iptables | less

If no iptables is found, install yum install iptables-services.

 

 

7. Set firewall policies

① Open ports to all addresses

Iptables-I INPUT-p tcp-m state -- state NEW-m tcp -- dport port number-j ACCEPT

/* The above commands are used temporarily, and will become invalid after Shutdown and restart */

Service iptables save/* Permanent storage */

② Prohibit access to a port from an IP address

Iptables-a input-s IP address to be disabled-p tcp -- dport port number-j DROP

③ Disable ping

Iptables-a input-p icmp-j DROP

④ Disable ping. You can ping other machines, but other machines cannot.

Iptables-a input-p 1 -- icmp-type 8-j DROP

⑤ Access from an IP address is not allowed

IP address-j DROP prohibited by iptables-a input-s

⑥ Delete firewall rules

Iptables-D type row number

 

8. compressed files

Tar-cvf test.tar test.txt/* package the test.txt file in the Directory into test.tar */

Tar-czf test.tar.gz test.txt/* package the test.txt file in the Directory into test.tar, and compress it with gzip, and name it test.tar.gz */

 

 

9. decompress the file

Tar-xvf test.tar/* decompress the tar package */

Tar-xzvf test.tar.gz/* decompress tar.gz */

 

Tar-xvf test.tar-C target address/* decompress the tar package to the specified directory */

 

 

10. Move files

Mv source file or source directory target file or target directory

 

 

11. Copy files

Cp source file target file

  12. Set Environment VariablesVi/etc/profile/* all global users */   13. Set auto-start upon startupVi/etc/rc. d/rc. local

 

 

14. Change the File Permission

Chmod 777 file/* readable and writable executable */