of following best describes learning management system

From the previous study, we know that the disk can be divided into multiple partitions, each partition can be advanced format after the formation of a file system. So how do you create partitions in a Linux system?Use the FDISK command to create a partitionThe syntax format is: fdisk [-l] Device file name ( cannot add number )-L: Displays the contents of all partitions on the specified hard disk. Without th

can hold is 16GB, which is consistent with the file restriction table results. However, this method is not applicable when the block size is 2KB or 4KB, because the block larger than 2KB will be limited by the EXT2 file system itself, and the calculation results and the restriction table.(3) Super blockwhere this block records information about the entire file system, the main records are:Block and the tot

1. Process address spaceIn Linux, processes do not directly manipulate physical memory addresses, buteach process is associated with a virtual address spaceMemory page is the Memory Management Unit (MMU) can be managed by the minimum address unit machine architecture determines the size of the page, 32-bit system is usually 4KB, 64-bit system is usually 8KB memor

Process Management-Processor Scheduling I. Basic concepts of scheduling 1. Job Scheduling Job Scheduling is also calledMacro or Advanced scheduling. Select a job in the backup status and create a process. Generally, most batch processing systems are equipped with job scheduling. In other systems, Job Scheduling is usually not required. The Job Scheduling frequency is low, usually several minutes. 2. Process Scheduling Process Scheduling is an operatio

");} // calculate the position of the next vertex nextpointreturn nextpoint;} class ball {private rope; private point currentpoint; ball (rope, point currentpoint) {This. rope = rope; this. currentpoint = currentpoint;} public void move () {currentpoint = rope. nextpoint (currentpoint); system. out. println ("moved... "+ currentpoint );}} /* The following scenario is designed in an object-oriented way. 2.

How messages are delivered Two primitives for communication between processes Send (Destination,message) Receive (Sourse,message) Synchronization of Message Delivery Three modes of synchronization Blocking receive Addressing in message delivery Indirect addressi

line to the file headerCtrl+d: Turn half screen at the end of the fileCtrl+u: Turn half screen to file headerString search:/keyword: From the file header to the tailKeyword: from the tail of the file to the headerN: Shows the next foundN: Displays the last foundExit Esc+q4, Info Command, there is a hyperlink document, info is the information page, provide the author, version, when the release of more detailed information, man manual is to tell you how to use,5, README; most programs have a corr

" - Represents a continuous time range. such as "0 5 * * 1-6 command", which represents the execution of commands from Monday to Saturday 5:0 A.M. */n Represents how often it is executed. Like "*/10 * * * * * * * * * * * * * * * * * * * * * * * * * * * command" time meaning TD valign= "Top" width= "196" > Execute command at 22:45 45 22 * * * command 0 17 * * * 1 command

increase the additional overhead of the system　　　　　　Hardware methodsControl synchronization and mutual exclusion by shielding interrupts or by using specialized machine directivesReduces system overhead, requires too strong hardware constraints, and can cause process starvation and deadlock, without becoming a common solution　　　　　　Signal Volume method (emphasis)Special support by the operating

,moosefs, MogileFS, Hdfs,gfs, GlusterfsTo create a file system:MKFS ( It is actually called according to the different file types, corresponding to the other formats of the/sbin under MKFS.EXT2,MKFS.EXT4, and so on-T)MKFS-T type DEVICE Example: Mkfs–t ext4/dev/sdb1 =mkfs.ext4/dev/sdb1MKE2FS ( Special Management tool for Ext Series file system):mke2fs-t {EXT2|EXT3|EXT4} DEVICE-B block:1024, 2048, 4096- l ' L

read the time of the last Anacron execution in/var/spool/anacron/cron.daily.(2) compared with the current time, if two times difference is more than one day, perform cron.daily work.(3) Performing this work is only between 03:00-22:00.(4) The forced delay time is 5 minutes when performing the work, and then a random delay of 0-45 minutes(5) Use the Nice command to specify the default priority and use the Run-parts script to execute all executables in the/etc/cron.daily directory.Note: Anacron w

not need to enter the passwordThe content format of the password file/etc/rsyncd.passwd is: Username:password, the permission is The command to start the service is: Rsync–daemonDefault to use/etc/rsyncd.conf This configuration file, you can also specify the configuration file rsync--daemon--config=/etc/rsyncd2.confThe available options are: Rsync–daemon--help rsync ip::test:/directory 1/directory 2: Synchronizing data using the test moduleRsync-av--password-file=filename/Directory/directory:

environment in which there is a route, there is a signal controller, because the semaphore is an enumeration, do not instantiate here, directly in the controller associated with a semaphore can be.The test code is as follows://Package com.fylx.test; Public classtest{ Public Static voidMain (string[] args) {//TODO auto-generated Method StubString[] Lamps =NewString[] {"s2n","s2w","e2w","E2s","n2s","n2e","w2e","w2n","s2e","e2n","n2w","W2s" }; for(String lamp:lamps) {//according to the signal, in

that a machine can directly connect to the B machine's 22 port.Take my own environment for example, a machine for windos host, IP for 192.168.226.1b Machine for VMware inside LINUX1, there are two network cards, ENS33 IP for 192.168.226.129ENS37 to 192.168.100.1C Machine for virtual machine linux2, IP for 192.168.100.100Now how to configure can let the host SSH connection linux2?1. Route forwarding is still turned onecho "1" >/proc/sys/net/ipv4/ip_forward2 Configuring routing RulesA on the exec

Commands for System Management classescommands for the System Management class : # shutdown (command) [option] ... Time -r : Restart h: shut down -c : Cancel restart or shutdown command time format: now Span style= "font-size:14pt" >

/s txcmp/s rxmcst/s12:10:01 AM Lo 0.00 0.00 0.00 0.00 0.00 0.00 0.0012:10:01 AM eth0 0.62 0.04 0.04 0.01 0.00 0.00 0.0012:10:01 AM eth1 0.59 0.01 0.04 0.00 0.00 0.00 0.00RXPCK/S indicates the number of packets received per second txpck/s Indicates the number of packets per second rxkb/s amount of data received per second txkb/s amount of data sent per second5 free View memory conditionTotal used free shared buffers cachedmem:1906900 274296 1632604 232 24268 111232-/+ buffers/cache:138796 176810

rootfs: Root file System /boot: System startup related files such as kernel, INITRD, and Grub (bootloader) /dev: device files Device files: block devices: Random access, data blocks Character Devices: Linear access, by character device number: Master device Good (major) and secondary device number (minor) /etc: Config file / Home: The user's home directory, each user's home directory usually

常关闭指定vm650) this.width=650; "src=" Https://s4.51cto.com/wyfs02/M00/91/40/wKioL1j0w3byHQJNAAAzHo2YNoo260.png "title=" Screenshot from 2017-04-17 12-06-32.png "alt=" Wkiol1j0w3byhqjnaaazho2ynoo260.png "/>Virsh Destroy Vmname # #强行结束指定vmVirsh Create Vmname.xml # #临时恢复指定vm, Vmname represents the front-end management fileVirsh Define Vmname.xml # #永久恢复vmVirsh undefine vmname # #删除vm前端管理, storage not deleted650) this.width=650; "src=" Https://s2.51cto.com/w

Let's review the previous section:1. Set Password command passwd2. User Information Modification Command usermod3. User Delete command Userdel4. Job: Modify User1 User ID 505, home directory to admin, user Group is admin, finally delete user1 userUsermod–u 505–d/home/admin–g Admin User1Userdel user1In this section, we continue to talk about user management-related commands1. Add User group GroupaddThe use of this command is simple groupadd groupnameAf

changes the destination address of the locally generated package. The postrouting chain changes its source address before the package leaves the firewall.The mangle is primarily used to modify the TOS (type Ofservice, service type), TTL (Time tolive, lifetime) value of the packet, and to set the mark mark for the packet to implement QoS (Quality of service,Service quality) tuning and Policy Routing applications are not widely available due to the need for appropriate routing device support. Fiv