Which RunLevel does the graphical interface start with?

1. Which runlevel does the graphical interface start with? And what is the operating level of the command line mode we usually use? What does the other runlevel mean, in addition to the two common levels of graphics and command-line mode? How do I change the operating level of the system?

A: (1) graphical interface running level is 5

(2) command-line mode run Level 3

(3) 0-off (never set as default)

1-Single user mode

2-Multi-user mode without NFS (Network file system)

3-Full multi-user mode

4-Reserved

5-x window, graphical user interface

6-reboot (never set as default)

(4) Change the runlevel with the command init command

Example: Shutdown--init 0

Restart --init 6

2. How many TTY does Linux default to boot altogether?

A: The default boot 6 TTY, respectively, with F1-F6 switch.

Reference: http://www.bkjia.com/Linuxjc/871270.html

3. How do I install a graphical desktop using the Yum tool? What if the installed graphics do not display Chinese?

A: (1) Before installing the graphics table, you need to install some packages using the Yum tool:

# Yum Grouplist (displays information such as installed, available installation, etc.)

# lang=en (using English)

# yum Grouplist (show grouplist info again)

# yum Groupinstall-y "desktop" (Install desktop)

# Yum groupinstall-y "x Window" (Install X Window)

# init 5 (= = startx, open Desktop)

# runlevel (View the run level of desktop mode)

(2) If the installed graphics desktop does not display Chinese, we can use "System"--"administration"

--"Add/remove software"--Enter root password--select "Chinese support"

--"Apply"--Reboot the system--"update name".

Reference: http://jingyan.baidu.com/article/da1091fbd5b0e3027849d6d1.html

4. To exit the terminal interface, which shortcut can I use in addition to exit? Would you like to cancel an incorrect command? How do I pause a task that is running on a current terminal?

Answer: Ctrl+d exit terminal; Ctrl + c cancel command; Ctrl + Z pause the task and use the Jobs command to view the suspended task.

5. What command can I use to view the Help documentation for a command?

Answer: (1) Type command name # # give a short explanation of the command

(2) which command name # # View the location of the command

(3) help command name # # to get the command's Aid document

(4) Command--help # # Get help documentation for commands

(5) Man command name # # View official documentation for a document

Reference: http://jingyan.baidu.com/article/14bd256e4d4561bb6d2612fc.html

6. What is a hidden file or directory under Linux? How do I see if a directory has hidden files or directories?

A: (1) There is a dot "." In front of the hidden file or directory name under Linux, such as ". SSH"

(2) The LS-A command can view all files or directories, including hidden

7. What are the most commonly used commands for Linux systems? In which directory will the system log be logged?

Answer: (1)/urs/bin/# # many Apps

/urs/sbin/# # Some admin programs for super users

/usr/local/bin/# # Local Add-on command

(2)/var/log/

Reference: http://www.cnblogs.com/wen858636827/archive/2012/12/26/2834373.html

8. Use one command: Let other hosts not ping your Linux.

Answer: Disable ping: Echo 1 >/proc/sys/net/ipv4/icmp_echo_ignore_all

Reference: http://blog.csdn.net/hzhsan/article/details/44595387

9. Please write down the commands you know to restart the Linux system.

Answer: (1) Init 6

(2) Reboot

(3) shutdown-r now # # parameter R indicates reboot

10. How do I forget the root password?

A: If you do not have a grub password, we can reset the root password using single-user mode, or use rescue mode to reset the root password, regardless of the grub password.

What is the relationship between MBR and grub?

A: When the MBR is started by the hard disk, the BIOS is usually the first sector to turn to the first hard drive, that is, the master boot Record (MBR), the only thing it does is to load the second boot loader grub, and its role is actually to elicit more advanced functionality to allow the user to mount a specific operating system. Grub transfers control over the machine to the operating system.

12. What command can I use to sort the files and directories in the specified directory by time?

Answer: The CD enters the directory with the following command:

LS-LRT

-L Use a long listing format is displayed as a long list (detail mode)

-t Sort by modification time sorted by modified (newest in front)

-R reverse order while sorting (reverse order)

13. If you do not set the password for grub when installing the system, how do I set it up in the system? Clear text How to set, how to set ciphertext?

Answer: (1) Edit Grub Profile: vi/etc/grub.conf

Insert a line below the line where "Splashimage" is located, and write: password=abc123

set the grub password to abc123

then insert a line above the "root (hd0,0)" line, and write: Lock

exit after saving.

(2) plaintext encryption is (1); ciphertext encryption is as follows: To use MD5 to encrypt it. In the terminal, enter:

Grub-md5-crypt Enter, then the system will require two times the same password, then the system will output MD5 code.

Copy the generated MD5 ciphertext, and then set the global or menu secret in accordance with the password--md5 MD5 ciphertext format

yards, Save the exit and restart the computer.

reference: 1. Http://wenku.baidu.com/link?url=zBIuky6pSpoVP2kz8rwjCsy2XZkUZDWCnnfV

cqwg1ml-54d8cql4wynhecbo2qik0xm0yjcaq_ph6wp9qzkzni1s2uvblhetw9io0vqgs7s

2.http://kerry.blog.51cto.com/172631/149977/

14. How do I check which terminal the current account is logged on to?

Answer: (1) Use command TTY

(2) using the command who am I

(3) using the command W

(4) Use the command

Reference: http://blog.sina.com.cn/s/blog_5f99444c01015ntj.html

15. How do I see CPU and memory details?

Answer: (1) View CPU information using command: Cat/proc/cpuinfo

(2) View memory information using command: Cat/proc/meminfo

Reference: https://zhidao.baidu.com/question/155943069.html

16. In which directory is our Linux system under the rescue mode of CD-ROM? What do I need to do to use the passwd command?

Answer: (1) After entering rescue mode, the local Linux system will be mounted to the directory/mnt/sysimage/directory

(2) to use the passwd command to modify the root password modification first switch to the local Linux system environment, using the command:

chroot/mnt/sysimage/

Which RunLevel does the graphical interface start with?