Programmer Think

Hand-Making Wheels: Implementing EventBus Based on RedisIntro#Last time we built a simple memory-based EventBus, but it would be inappropriate to cross-system, so we have this Redis-based EventBus exploration. The implementation of this paper is based on StackExchange.Redis. RedisEventStore Implementation#Since it is naturally impossible to reu ...

TCP Wrappers TCP Wrappers is a firewall-like mechanism managed by two files /etc/hosts.allow /etc/hosts.deny Not all software can be managed through these two files, only the following two software can manage firewall rules through these two files: Services managed by super daemon (xinetd) Services supporting libwrap.so m ...

This paper demonstrates user configuration, sudo privilege configuration, network configuration, firewall closure, JDK tool installation and so on with K-Master server infrastructure configuration as an example. Users need to complete the basic environment configuration of KVMSlave 1 ~ KVMSlave 3 servers by referring to the following steps. ...

Setting up the Saltstack environment, we found in the process that it is very different from ansible, the functions are divided into module s and state s, which become more complex.First, you need to install master, minion, and get the fqdn of the machine because of the Zeromq used in the communication mode. This virtual machine is easy to tre ...

Remote Access Control / The two files, etc/hosts.allow and/etc/hosts.deny, control remote access by which a client of an IP/IP segment can be allowed or prohibited to access Linux. sshd:172.25.254. :spawn echo `date` from %c to %s >> /dev/pts/1 iptables Summary: Linux packet filtering software. Three watches and five chains ...

Background Recently, at 05:00 a.m., I always get warnings from the SQL firewall: group_name id user host db command time info state BASE 1059712468 xx xx.xx.xx.xx aea Query 34 UPDATE approve SET operator = 0', operator_name ='system', comment ='departure', status ='1'WHERE (id = 48311') updating When I first saw this data, the first react ...

Step 1. Preparations Close the firewall; install MySQL dependent on the libaio library; download, unzip, rename the MySQL executable; and prepare for new user groups and users will not be covered here. The executable directory is/data/mysql57 Instructions to add users and groups groupadd mysql useradd mysql -g mysql Step 2. Add environm ...

Install and deploy Zabbix agent on Windows Server Download and unzip to the specified directory Zabbix download page: https://www.zabbix.com/download Current latest version of zabbix-agent Download https://www.zabbix.com/downloads/3.4.0/zabbix_agents_3.4.0.win.zip Unzip to disk C and rename the directory zabbi ...

Network configuration under linux 1. What is IP ADDRESS internet protocol ADDRESS ##Network process address ipv4 internet protocol version 4 ip It consists of 32 0,1. 11111110.11111110.11111110.11111110=254.254.254.254 2. Subnet mask Used to divide the network area The digital bits on the ip corresponding to the non-ze ...

Build ES development environment.Installation instructions Environment: centos7 Java : java8 elasticsearch-6.5.4 Download address $ cd ~ $ cd download $ wget https://artifacts.elastic.co/downloads/elasticsearch/elasticsearch-6.5.4.tar.gz Pre-installation Conditions Note: The article has been configured by default version ...