Manage hierarchical data using MySql

Summary We know that relational database tables are better suited for flat lists than for hierarchical data with parent-child relationships that can be directly managed like XML. First, define the hierarchy we are discussing, which is a set of data where each entry can have only one parent and zero or more children (the only exception is the ...

Posted on Tue, 17 Dec 2019 21:15:50 -0500 by Michael Lasky

yum command, build shared warehouse, blacklist of yum

1.yum command yum clean all # Clear the original yum cache yum install [Software name] # Installation software yum remove [Software name] # Uninstall software yum repolist # List warehouse information yum list [Software name] # V ...

Posted on Fri, 13 Dec 2019 13:09:55 -0500 by contex

fdisk and parted partition

There are two types of linux partitions I contact: one is using fdisk partition, and the other is parted partition. The former is for MBR mode partition, and the latter is for GPT mode partition fdisk partition: Fdisk - L ----- > view disk informationFdisk / dev / SDC -- > select the disk to operate (eg:/dev/sdc) a toggle a bootable fla ...

Posted on Tue, 03 Dec 2019 21:12:01 -0500 by chord

Operation and maintenance enterprise practice -- DR (direct routing) mode of LVS

I. construction of DR mode 1,server1: 1. Change yum source vim /etc/yum.repos.d/rhel-source.repo [rhel-source] name=Red Hat Enterprise Linux $releasever - $basearch - Source baseurl=http://172.25.60.250/iso enabled=1 gpgcheck=1 gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-redhat-release [LoadBalancer] name=LoadBalancer baseur ...

Posted on Mon, 25 Nov 2019 15:45:14 -0500 by barbs75

Ambari cluster construction

This paper takes ambari-2.7.3.0, HDP-3.1.0.0, HDP-UTILS-1.1.0.22 and HDP-GPL-3.1.0.0 as examples to build ambari cluster. I. download the corresponding version of the image package wget http://public-repo-1.hortonworks.com/ambari/centos7/2.x/updates/2.7.3.0/ambari.repo wget http://public-repo-1.hortonworks.com/ambari/centos ...

Posted on Thu, 21 Nov 2019 10:17:11 -0500 by JasonTC

Linux basic command -- slabtop display kernel strip information

slabtop slabtop displays detailed kernel strip cache information in real time. It displays a list of top-level caches sorted by one of the listed sort criteria. It also displays a statistics header filled with slab layer information. The application scope of this command: RedHat, RHEL, Ubuntu, CentOS, Fedora, SUSE, openSUSE. 1. Grammar ...

Posted on Thu, 14 Nov 2019 15:29:46 -0500 by studgate

Version 5 - encapsulation of virtual machines

1. Install virtual machine 2. Set the basic configuration of virtual machine (1) delete files Because the mac address does not match, if the file is not deleted, an error will be reported when restarting the network. cd /etc/udev/rules.d/ rm -f 70-persistent-net.rules (2) set ip cd /etc/sysconfig/netw ...

Posted on Sat, 19 Oct 2019 17:33:48 -0400 by darklight

Find Linux distribution name, version, and kernel details

This article changes from Linux China This guide describes how to find the Linux distribution name, version, and kernel details. If your Linux system has a GUI interface, you can easily find this information from the system settings. But in command-line mode, it's hard for beginners to find these detail ...

Posted on Wed, 02 Oct 2019 17:40:21 -0400 by fusioneko

Linux System Batch Configuration Script

System Batch Configuration Script ManualRequirements for uselinux Operating System (RHEL, kylin, Crystal Rock available)The local computer expect command is availablessh, scp commands are availableScript Composition and Function DescriptionBoot script - config.shThe script guides the execution of the entire script combination, prompting the use ...

Posted on Sat, 29 Jun 2019 16:46:58 -0400 by payney

SCP error-bash: scp: command not found

Environment: RHEL 6.5 Use the scp command to report errors: [root@oradb23 media]# scp /etc/hosts oradb24:/etc/ -bash: scp: command not found View openssh related packages: [root@oradb23 ~]# rpm -qa openssh* openssh-5.3p1-94.el6.x86_64 openssh-server-5.3p1-94.el6.x86_64 It was found that the server did not install openssh's client by default. yu ...

Posted on Sun, 03 Feb 2019 23:09:16 -0500 by millwardt