Linux

Linux file permissions and access controlAccess file User 3 class: 文件所有者 同组成员 其他人Permissions---------(rwx) corresponds to 3 categories of users in turnfile:6rw 4r 0 x1dir: 7rwx 5r-x 0Default Permissionsumask内部命令 用来生成数字 umask+default =file666

OpenSSL command-line tools:Numerous sub-commands to achieve a variety of security encryption functions;Standard command:ENC,DGST,CA,REQ,GENRSA,RAND,RSA,X509,PASSWD, ...Symmetric encryption Command: ENCA symmetric encryption algorithm is provided for

The first two sections have taught you how to install a Linux system on a virtual machineIn this section, we will learn about the directory structure of Linux, describe the entire system architecture of Linux, and familiarize yourself with

网络很重要！网络是一切网络服务的基础，没有网络，就不会有今天的BTA。现在的服务器主要是linux，所以linux的网络配置和管理很重要。One, the introduction of network communicationThe three elements of communication are: IP address, mask, route.IP and netmask are required, and with these two conditions, local

One, common Operation command 1. Linux command syntax formatcommand [options] [parameters]A few notes:The ① option determines the different operations, and the parameters determine the Action object② Case Sensitive③ commands, options, parameters

"Problem description"Due to the recent use of the Spring Eureka Registry Service, and the office every night to power down, every morning after the need to manually start the Eureka service is very troublesome.Need to implement: power on the

File Management file system and directory structureFiles and directories are formed into a single inverted tree structure. Root file system Rootfs root filesystemRootfs:/etc/,/usr,/var,/root,/home,/devFile system hierarchy LSB Linux standard BaseFhs:

Objective: Between the same machine to achieve the common user-free login: NN01 user1-Free login User2 Between the different machines to achieve the common user-free login: NN01 user1-free landing NN01 user1 I. To achieve a free

Linux various versions(like the kernel, the software, probably the configuration file is not the same)History is as followsRedhat Fee System: Service charge, but system does not chargeSlsDebian is a Debian Project founder Ian Murdock and his wife

Netstat-na# shows all active network connections to the server netstat-an | Grep: the|sort# only shows active network connections to 80 segments, and 80 is the HTTP port, which is useful for Web servers and sorts the results. It is useful for you to

Interrupt classificationIn Linux systems, interrupts are divided into: Hard interrupt: An interrupt that is generated by an external device or that performs an exception that needs to be processed quickly. such as missing pages interrupt,

1. Purpose:Change the password for user Duan2. Method:(1) Current user is Duan1. Login account Duan2. Execute command passwd3. Prompt for Unix passwd, enter Duan's original password, and enter the new password two times.(2) switch to root user

A. Find commandThe Find command in a Linux system is useful and convenient when locating files. It can find files based on different criteria, such as permissions, owner, date/time modified, file size, and so on. In this article, we'll learn how to

What is 1.Nginx?Nginx is a high-performance HTTP and reverse proxy Server software, the first open source version was born in 2004, although the birth later but after more than more than 10 years of development, has become very popular Web server

1. InstallationExecute yum-y Install VSFTPD2. Check if VSFTPD:RMP-QA is installed | grep vsftpd Default configuration file/ect/vsftpd/vsftpd.conf3. Create a virtual userA. Choose to create an FTP folder under the root or user directory: mkdir

UseOutput socket statistics, when no parameters are displayed by default is the list of established socketsUsagess [options] [ FILTER ]Common options-H,--helpDisplay Help information-V,--versionDisplay version Information-N,--numericNumbers in lieu

RPM Package ManagerInstall the compiled package binary package methodRPM-IVH Lynx # rpm Install RPM-E Lynx # Uninstall Package rpm-e Lynx--nodeps # force Uninstall RPM-QA # View all installed RPM Packages Rpm-qa |

Version requirements: Linux CentOS 6.8 tomcat8.5.9 (not available) JDK 8u141 Jenkins 2.107.1Introduction?? Continuous integration (CI) is the cornerstone of modern software development, and it changes the team's understanding of the entire

Touch File # Create a blank file rm-RF Directory Name # does not prompt to delete a non-empty directory (-r: Recursive Delete-f Force) Dos2unix # Windows text to Linux text Unix2dos # Linux text to Windows text eNCA filename # View coded install Yum

1. Through top, find the process ID that consumes high CPU2.As shown in Java, the process ID is ' 52554′, and then the top command is used to monitor all threads in the process separately:top-p52554 -H3, (then see which Java thread CPU high, which