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1. Model Introduction Definition of patterns Define the framework of the algorithm in an operation and defer some steps to subclasses. It enables subclasses to redefine some specific steps of the algorithm without changing the structure of the algorithm. Use scenarios of patterns When multiple subclasses have common methods and the logic ...

No important system can ignore server security, especially in the public cloud. There are many online tips and tutorials on this subject. Here we only look at a few basic and common best practices. Several security measures to be implemented after system configuration is completed Take Ubuntu 16.04 as an example: 1. Update the kernel ...

iptables rule backup and recovery 9 zone s of firewalld   System CTL disable iptables boot on System CTL stop iptables turn off service System CTL enable firewalld boot System CTL start firewalld opens the service View all zone s [root@glinux-01 ~]# firewall-cmd --get-zones block dmz drop external home internal public trusted work ...

Oracle database server DG can not complete data synchronization after restarting from the database. The specific error information is as follows: I. Misinformation alter log error reporting *********************************************************************** Fatal NI connect error 12547, connecting to: VERSION INFORMATION: TNS f ...

VSFTP startup failure - Failed to start Vsftpd ftp daemon The error is as follows [root@host-liu vsftpd]# systemctl status vsftpd.service vsftpd.service - Vsftpd ftp daemon Loaded: loaded (/usr/lib/systemd/system/vsftpd.service; disabled) Active: failed (Result: exit-code) since Tue 2018-07-03 10:09:23 CST; 2min 3s ...

1. Download Compressed Files on mysql Official Website https://dev.mysql.com/downloads/mysql/5.7.html#downloads 2. Copy the downloaded files to the / opt directory of centos system III. Start installation 1. Decompress mysql-5.7.22-linux-glibc2.12-x86_64.tar.gz [root@centosDemo opt]# tar -zxvf mysql-5.7.22-linux-glibc ...

I. Installation and testing [root@VM_0_10_centos ~]# yum install subversion View svn version [root@VM_0_10_centos ~]# svnserve --version svnserve, version 1.7.14 (r1542130) compiled Apr 11 2018, 02:40:28 Copyright (C) 2013 The Apache Software Foundation. This software consists of contributions made by many people; see th ...

Network configuration under linux 1. What is IP ADDRESS internet protocol ADDRESS ##Network Protocol Address ipv4 internet protocol version 4 1.2x32 ip It consists of 32 zeros and 1. 11111110.11111110.11111110.11111110 = 254.254.254.254 2. Subnet mask Used to divide the network area The number on the ip corresponding to t ...

The author recently wrote a system for uploading files through ASP.NET MVC4 WebApi, jQuery, ajax and FormData (see Multi-file uploading method based on ASP.NET MVC4, WebApi, jQuery and FormData Testing everything on your laptop, but publishing it to the client server (cloud server, Windows Server 2012) Operating system, with strong firewall p ...

Summary Report errors: ERROR: Cannot open control pipe - NT_STATUS_INVALID_PARAMETER Reason: After doing a lot of research on code, hacker attacks and reading a lot of websites and even discussing topics with MS, the root cause of the problem is that Microsoft has deleted SMB1.0 from Windows 8.1 and Windows Server 2012 ...