jenkins是一个开源持续集成工具
目标：jenkins从gitlab、github、svn拉取代码，编译部署到远程服务器tomcat中/k8s集群中

1、服务器准备
服务器安装jdk、maven、git，这里全部用yum安装
yum install java-1.8* maven git

2、查看安装版本
java -version
openjdk version "1.8.0_262"
OpenJDK Runtime Environment (build 1.8.0_262-b10)
OpenJDK 64-Bit Server VM (build 25.262-b10, mixed mode)

mvn -version
Apache Maven 3.0.5 (Red Hat 3.0.5-17)
Maven home: /usr/share/maven
Java version: 1.8.0_262, vendor: Oracle Corporation
Java home: /usr/lib/jvm/java-1.8.0-openjdk-1.8.0.262.b10-0.el7_8.x86_64/jre
Default locale: en_US, platform encoding: ANSI_X3.4-1968
OS name: "linux", version: "3.10.0-1062.4.2.vz7.116.7", arch: "amd64", family: "unix"

git --version
git version 1.8.3.1