Linux Foundation Knot Course Assessment

Tag: Boot ack Linux in CTR file system shutdown date Start command

Brief answer

Shell Basics:
1 Please describe the file types in Linux?
-: Normal file
D: Catalog file
B: Block device files
C: Character device file
P: Pipeline File
L: Soft link file (symbolic link file)

2 What is the difference between a symbolic link and a hard link?
After the system deletes the source file, the symbolic link is not accessible, and the hard-link file still exists to be accessible.
Symbolic links can be partitioned across disks, and hard links are not available.

Users/Groups/permissions:
1 The user's account and password information to protect what files exist? What does each field in the file mean?
The account is guaranteed to exist:/etc/passwd
[User Name] Password [user ID number UID] [group identification number GID] [User full Name] [Home directory] [Shell Type]
Password is guaranteed to exist:/etc/shadow
[User Name] [Encrypt password] [Date Modified] [Number of days before the password is allowed to be replaced] [Number of days the password needs to be replaced] [Number of days for password change warning] [Number of days before the account is deactivated] [user account expiration Date] [Reserved Fields]

What does 2 su mean when switching users,-and-C?
-: Change Login shell
-C: Executes a command and then exits the current user environment

3 Please describe the meaning of the file and directory 9-bit permission bit
R: Readable; W: writable; X: Executable
The first three bits are the permissions of the user owner;
The middle three bits are the permissions of the user group;
The latter three bits are the permissions of the other owner

Package Management:
How many databases are there on the 1 rhel6 CD? How to configure a repository with a local disc
5 x
1. Display the disc's directory
2. Edit with the VI command
[Server]
Name=server
baseurl=file:///media/"CD-ROM directory"/server
Enabled=1
Gpgcheck=0
3. Use Yum repolist all to see if the repository is configured successfully

Storage Management:
1 What are the steps required to use disk space in Linux?
1. Partitioning the disk using the FDISK command
2. Format with the MKFS command (create file system)
3. Mount using the Mount command

What are the advantages of 2 LVM compared to single disk management?
1. Can change the size of the logical volume arbitrarily
2. Can span partitions

3 Please describe the entire process of configuring disks with LVM
1.PVCREATE/DEV/SDB/DEV/SDC Creating a physical volume
2.vgcreate VG01/DEV/SDB/DEV/SDC Creating a volume group
3.lvcreate-l 550m-n lv01 vg01 Creating a logical volume
4.MKFS.EXT4/DEV/VG01/LV01 Creating a file system
5.mount/dev/vg01/lv01/dir01 Mount

System boot:
1 Please describe the startup process of the Linux system.
1. Boot loader
2. Loading the kernel
3. Run the INIT program
4. Initial process
5. Login

What is the role of root, kernel, initrd in grub.conf 2?
Root: The first partition on a hard disk
Kernel: Kernel files and parameters
INITRD: Help kernel Initialize memory disk image file

3 Please briefly describe the basic meaning of the LINUX0-6 7 operations
0: Shutdown 1: Single User 2: No network
3: Cluster 4: Undefined 5: Graphical interface 6: restart

4 What is the role of chkconfig and service commands?
Chkconfig: Automatic Control Service
Chkconfig--level Run-level server on: Turn on server
Chkconfig--level Run-level server off: shutting down the server
Chkconfig-list Server: View server Status
Service: Manual Control Services
Service server start: Powering on the server
Service server stop: shutting down the server
Service Server Status: View server state

Process Management:

What is the difference between 1 kill 1234 and kill-9 1234? What is the role of Killall?
Kill 1234: Normal closing process with process number 1234
KILL-9 1234: Forcing the process to close process number 1234
Killall: Can kill the specified process

2 What is the difference between a process running in the foreground and the background? How does a process that is already running in the foreground switch to run in the background?
While the process is running in the foreground, it cannot operate on other processes, and the process hangs in the background to manipulate other processes.
CTRL + Z

Scheduled Tasks
1 How should the user's Crontab timer task be set? How should the output of the command be handled? How do I make a backup of Oracle users every Sunday 1 o'clock in the morning?

1. Open vi Editor with CRONTAB-E, edit content
2. Enter the contents of the scheduled task on the editor and save the Exit
3. Use Crontab-l to view the list
4.cat/var/log/cron/the user to see if the content was compiled successfully

0 1 * * 7 oracle/backup.sh

Kernel:
1 briefly describe the functionality of the kernel.
1. Pass the application request to the hardware
2. Can be a separate kernel module
2 How can I permanently modify the kernel parameters without rebooting the system?
1. Use the SYSCTL command to display all available values
2. Edit with the VI command
3. Refresh the load using the SYSCTL-P command

Linux Foundation Course assessment