Linux

1: Turn off SELinux and iptables (in the work scenario, if there is an external IP generally open iptables, high concurrency high traffic generally cannot be turned on)[[email protected] ~]$ grep SELINUX=disabled /etc/sysconfig/selinux

The most common is the Rdate serviceInstallation (CentOS for example):Yum InstallUsage:Time-b.nist.govAfter the execution of the above method time is synchronized. Some servers are not allowed to be separated for a period of time, so we have to add

"‘‘``The single quote "is equivalent to the contents of the content directly output." Does not take into account whether there are variable commands, etc.Double quote "" Only variable command will be output directlyAnti-quote ' ' both

User Add Modify Delete1 Useradd adding usersAdd a new user hehe, specifying a UID of 3000 and a home directory of/home/haha[[email protected] ~]# useradd -u 3000 -d /home/haha hehehehe:x:3000:3000::/home/haha:/bin/bash[[email protected] ~]# ls /home/

Document Viewing and modificationVi/etc/hostsI modify the modeESC Exit Modification: Q Normal exit (File not modified: q! Do not save exit: X/:wq Save ExitCat/etc/hosts Document ViewModify HostVi/etc/hosts Reboot RequiredModify

1. Virtual Machine Management CommandsVirsh-manager # #开启虚拟机管理器Virsh List # #显示正在运行的虚拟机Virsh List--all # #查看所有虚拟机Virsh Start Desktop # #打开虚拟机Virsh Shutdown Desktop # #正常关闭虚拟机Virsh desktory Desktop # #强行关闭Virt-viewer Desktop # #显示虚拟机2. Installation

I said last time how to build a Linux virtual machine environment, but there are a lot of problems after the completion, screen resolution is too small is one of them.To give you a comfortable working environment, let us now teach you two ways to

You must first understand the two most basic commands:Tail-n test.log query log at the end of the last 10 lines;Tail-n +10 test.log Query all logs after 10 lines;Head-n test.log Query log file in the first 10 rows of logs;Head-n -10 test.log query

Ifconfig eth0 Up | DownWrites IP configuration information to the configuration file/etc/sysconfig/network-scripts/ifcfg-eth0Service Network restartRoute Add | del default GW 192.168.1.1Route-n/etc/resolv.confPingHost Www.baidu.comTracerouteNetwork

1. Locking system Important files:The system operator may sometimes encounter situations where a file cannot be modified or deleted by the root user, most likely because the file is locked. The command to lock a file under Linux is Chattr, which

PwdCdSpecial directories. And..Absolute path and relative pathTouch creates a file if the file that you want to create already exists, update the file's creation time.RM-RF Force no prompt to delete files and directoriesMV Cut or rename filesCat

(1) cd/etc/vsftpd/(2) Vim vuser.list Create user Zhaosi and Liwu password are redhat (odd behavior account name, even behavior password)(3) db_load-t-T hash-f vuser.list vuser.db(4) File vuser.db(5) chmod vuser.db(6) Rm-f vuser.list(7)

Fifth chapter--text editor vimI. VIM common operation 1.Vim Introduction: Vim is a powerful full-screen text editor, the most commonly used text editor on Linux/unix, it is to create, edit, display text files.    Vim has no menu, only commands.

File lock is one of the most common inter-process synchronization mechanisms in Linux. Compared with sysv semaphores, file locks are easier to use (the trouble of sysv semaphores lies in its key Acquisition Mechanism ).Apue provides a detailed

The drive of a general character device is transformed into a misc device. The MISC device is not as troublesome as a character device. In the future, try to replace the scull. c driver with a misc device. #include #include #include #include

Reference: http://oss.org.cn/kernel-book/ldd3/ch09s03.html 13-pin led positive input, 25-pin led negative Driver code: Parport_drv.c #include #include #include #include #include #include

The IOCTL test is an advanced Note of the coolder (1). The underlying IOCTL processing can control all registers by means of shift !~   Main. c upper-layer application test code # Include # include # include # include # include # include

More and more profound understanding of the importance of the foundation, so I want to study a course well, cultivate 0.0001 battle force as the core competitiveness. The experts have stepped on this post. Please leave some suggestions. Main

Linux dynamic library search path     As we all know, the default search paths for Linux dynamic libraries are/lib and/usr/lib. After a dynamic library is created, it is generally copied to these

Now that you are trying to develop programs in Linux, some preparations are necessary, such as makefile and shell. Now you have learned how to write makefile, taking advantage of this learning opportunity, I looked at the current General makefile of