[Linux] RHCE exam preparation review network communication netstat and ping commands

netstat command netstat command comes from the abbreviation of the English phrase "network statistics". Its function is to display various network related information, such as network connection status, routing table information, interface status, NAT, multicast members, etc. netstat command is not only applied to Linux system, but ...

Posted by perrij3 on Sun, 22 May 2022 03:35:27 +0300

Detailed process of Dameng mpp + active and standby

1. Refer to DM for software installation steps_ dw. txt First node Second node EP01 (main) EP02 ((main) EP12 (prepare) EP11 ((standby) 2. Install mpp active / standby --------------------First node 0.101 (1) Initialize instance EP01 main library: ./dminit PATH=/dm8/dmdata DB_NAME=EP01 INSTANCE_NAME="EP01" PORT_NU ...

Posted by shane07 on Sat, 21 May 2022 02:25:45 +0300

[advanced] 34. docker deploys mall

Mall project is a set of e-commerce system, including front office mall system and background management system. It is implemented based on SpringBoot+MyBatis and deployed in Docker container. The front desk mall system includes home page portal, commodity recommendation, commodity search, commodity display, shopping cart, order process, mem ...

Posted by Flinch on Fri, 20 May 2022 22:49:00 +0300

Shell script integer value comparison, logic test, if statement

1. Conditional test operation [conditional expression] (1) document test[file or directory]-d: Whether the directory is directory (test) -e: Test whether the directory or file exists (Exist) -f: Test whether it is a file -r: Test whether the current user has permission to read, -w: Test whether the current user has permission to write -x: T ...

Posted by Sneo on Fri, 20 May 2022 07:41:43 +0300

Upgrade CentOS 7 to openssh 8.0 7.p1

Background summary OpenSSH (OpenBSD Secure Shell) is a set of connection tools for secure access to remote computers of the Openbsd program group. The tool is an open source implementation of SSH protocol, supports encryption of all transmissions, and can effectively prevent eavesdropping, connection hijacking and other network level attacks. ...

Posted by tbeinc on Fri, 20 May 2022 04:59:54 +0300

Use chroot to restrict SFTP users to the home directory

In this tutorial, we will discuss how to restrict SFTP users to their home directory or specific directory. This means that users can only access their respective home directories, not the entire file system. It is important to restrict users' home directories, especially in a shared server environment, so that unauthorized users will not pee ...

Posted by wih on Thu, 19 May 2022 14:27:23 +0300

Build enterprise data network disk step by step

Tip: after the article is written, the directory can be generated automatically. Please refer to the help document on the right for how to generate it Overview of Linux system operation and maintenance preface Enterprise network disk is an enterprise data network storage and management solution based on the concept of cloud computing ...

Posted by maseeha on Thu, 19 May 2022 00:17:04 +0300

Solve the problem that Oracle occupies too much disk

background After the database has been running for some time, the table space has been increasing, but the actual amount of data is not so large. Deleting data or truncate tables does not reduce the tablespace. This is because when the table space is insufficient, it will expand automatically, but it will not shrink automatically. terms of se ...

Posted by lorewap3 on Wed, 18 May 2022 03:56:25 +0300

Shell Programming Specification Variable Details (shell programming specifications in Linux, how scripts are executed, pipe symbols and redirections, shell variable types)

Preface Shell is a program written in C that serves as a bridge for users to use Linux. Shell is both a command language and a programming language. _The execution of Linux commands must depend on the shell command interpreter. Shell is actually a special program that runs in the Linux operating system. It is located between the kernel of ...

Posted by simonmlewis on Sun, 15 May 2022 20:50:07 +0300

Detailed introduction of crontab service for scheduled tasks under linux

1, Introduction to crontab 1. crontab is used to allow users to execute programs at fixed times or intervals If you need to implement the task scheduling function on linux platform, you can write cron script to implement it. Perform tasks at a certain frequency linux will start the crond process by default. The crond process does not need to b ...

Posted by lrsdsout on Sun, 15 May 2022 18:18:13 +0300