Linux System Introduction & partitioning & basic Commands (Admin01-2)

6.5.3 Cat <&0 >&1

Reads data from standard input stdin (0) and displays it in standard output stdout (1)

6.6 uname

View Kernel version Information

Uname-r
3.10.0-327. El7. x86_64
Major version minor version rhel7 64-bit operating system

6.7 Lscpu

Displaying CPU-related information

6.8 Cat/proc/meminfo

displaying memory-related information

6.9 history

View history Commands

6.9.1 history-c

Clear History Command

6.9.2 Grep-i Histsize/etc/profile

histsize=1000
Can modify the value of the histsize, to modify the history of the number of records, the work is generally changed to 10 bar

6.9.3!str

Executes the most recent command that starts with STR

6.9.4!n

Executes the nth command in the command history

6.10 Date

View current date and time
Date +%y Year
Date +%m Month
Date +%d Day
Date +%r Time
Date +%f Displays the day of the month in a delimited way

6.10.1 date-s "Yyyy-mm-dd HH:MM:SS"

Modify the system date and time

6.10.2 date-d "@1513046661"

1513046661 is a timestamp, and the date-d command can convert the timestamp to a recognizable date time

6.11 Command &

Put the command in the background and run it.

6.12 Jobs

View the background pending process

6.12.1 jobs-l

Show background process, more than jobs show a PID

6.13 FG

Back up the backstage process to the front desk

6.14 Killall Process Name

Kill a Process

6.15 Ln

Create a hard link that can only be created for files of the same partition

6.15.1 ln-s

Create soft links that can be created for different partition files and directories

6.16 Mans

Man 1 passwd#1 represents execution program or shell command
Man 2 sethostname#2 represents system call
Man 4 mem#4 represents device file
Man 5 passwd#5 representative text file
Man 8 halt#8 represents the Super command that only root can use

1 executable programs or shell commands
2 System calls (functions provided by the kernel)
3 Library calls (functions within program libraries)
4 special files (usually found In/dev)
5 File formats and conventions eg/etc/passwd
8 System Administration commands (usually only for root)

6.17 wc-l filename

How many rows are there in the statistics file

6.18 Netstat-anptu

View network Status
-A: List all processes
-L: A process that only lists the source in the Listen state
-N: Displayed in digital form
-P: Process name and PID information
T:TCP Connection
U:UDP Connection
6.18.1 the meaning of the Local address
0.0.0.0 means all the NICs on this machine
127.0.0.1 represents only loopback addresses

The meaning of 6.18.2 Foreign address

Indicates which client is accessing the

6.19 Route-n

View the server's routing table
Flags:ug means static route, u means no next hop for direct route

Route-n
Kernel IP Routing Table
Destination Gateway genmask Flags Metric Ref use Iface
0.0.0.0 176.47.3.254 0.0.0.0 UG 0 0 Enp3s0
172.25.0.0 0.0.0.0 255.255.0.0 U 0 0 0 Rhce
172.25.254.0 0.0.0.0 255.255.255.0 U 0 0 0 Rhce
176.47.3.0 0.0.0.0 255.255.255.0 U 0 0 Enp3s0
192.168.2.0 0.0.0.0 255.255.255.0 U 0 0 0 Private2

6.20 IP Addr

View all NIC information on this machine

6.21 DMESG

Display boot information for diagnosing system failures

6.22 dd6.22.1 backing up HDA's partition table

DD If=/dev/hda of=/tmp/mbr.back bs=512 count=1

Seven, commonly used shortcut keys 7.1 ctrl+alt+fn

can switch between TTY
Tty1: Graphical interface
TTY2~TTY6: Character Console

7.2 Ctrl + C

Terminating a running command

7.3 tab

command, PATH completion

7.4 ctrl+l

Clear Screen

7.5 Ctrl+u

Deletes the current cursor to the beginning of the line

7.6 ctrl+k

Deletes the current cursor to the end of the line

7.7 Ctrl+shift+t

Open a new label within the terminal

7.8 ctrl+r

Find history mode, enter characters to automatically match the hit command

7.9 ctrl+w

Delete a word forward

7.10 ctrl+f

Move one character forward

7.11 Ctrl+b

Move backward one character

7.12 Alt+f

Move forward one word

7.13 Alt+b

Move one word backwards

7.14 Ctrl+t

The cursor position is swapped with the previous two characters

7.15 Esc+d

Delete a word after the cursor

7.16 Ctrl+s

Perform a screen lock

7.17 Ctrl+q

Cancel Screen Lock

Linux System Introduction & partitioning & basic Commands (Admin01-2)