安装jdk

在usr下创建java目录，使用命令下载jdk压缩包。这里是安装在/usr/java，或者可以使用yum安装到/usr/lib/jvm。

$ wget --no-check-certificate --no-cookies --header "Cookie: oraclelicense=accept-securebackup-cookie" http://download.oracle.com/otn-pub/java/jdk/8u102-b14/jdk-8u102-linux-x64.tar.gz

或者在本地先下载好再使用scp命令上传

$ scp /本地路径/jdk-8u102-linux-x64.tar.gz 登录用户名@服务器ip:/usr/java

解压完删除压缩包

$ tar xvf jdk-8u102-linux-x64.tar.gz

配置环境变量，将以下脚本添加到/etc/profile文件的末尾

JAVA_HOME=/usr/java/jdk1.8.0_102
JRE_HOME=/usr/java/jdk1.8.0_102/jre
PATH=$PATH:$JAVA_HOME/bin:$JRE_HOME/bin
CLASSPATH=.:$JAVA_HOME/lib:$JRE_HOME/lib
export JAVA_HOME JRE_HOME PATH CLASSPATH

最后reboot重启，执行java -version，结果显示已安装成功

$ java -version
java version "1.8.0_102"
Java(TM) SE Runtime Environment (build 1.8.0_102-b14)
Java HotSpot(TM) 64-Bit Server VM (build 25.102-b14,mixed mode)

安装jenkins

添加jenkins库

$ wget -O /etc/yum.repos.d/jenkins.repo http://jenkins-ci.org/redhat/jenkins.repo
$ rpm --import http://pkg.jenkins-ci.org/redhat/jenkins-ci.org.key

接下来使用yum命令来安装

$ yum install jenkins

下载rpm包过程中报错

Downloading Packages:
http://pkg.jenkins.io/redhat/jenkins-2.16-1.1.noarch.rpm: [Errno 14] PYCURL ERROR 18 - "transfer closed with 66371436 bytes remaining to read"
Trying other mirror.


Error Downloading Packages:
  jenkins-2.16-1.1.noarch: failure: jenkins-2.16-1.1.noarch.rpm from jenkins: [Errno 256] No more mirrors to try.

大概就是下载速度太慢关闭了，这里的解决办法是多次执行install直到下完或者还是到自已机器下载再上传到rpm所在目录，下载链接http://pkg.jenkins-ci.org/red...，我的rpm目录是/var/cache/yum/x86_64/6/jenkins/packages。

执行以下命令，可以看到jenkins已经是开机自启动的系统服务，它在/etc/init.d目录下生成了jenkins文件

$ chkconfig --list | grep jenkins

jenkins 0:关闭 1:关闭 2:关闭 3:启用 4:关闭 5:启用 6:关闭
jenkins的war包存放在/usr/lib/jenkins目录下，配置文件jenkins在/etc/sysconfig，我这里修改端口为8888

## Type:        integer(0:65535)
## Default:     8080
## ServiceRestart: jenkins
#
# Port Jenkins is listening on.
# Set to -1 to disable
#
JENKINS_PORT="8888"

可以看到jenkins的主目录

## Path:        Development/Jenkins
## Description: Jenkins Continuous Integration Server
## Type:        string
## Default:     "/var/lib/jenkins"
## ServiceRestart: jenkins
#
# Directory where Jenkins store its configuration and working
# files (checkouts,build reports,artifacts,...).
#
JENKINS_HOME="/var/lib/jenkins"

jenkins创建job和slave都会在这个目录下生成数据，现在是空的，数据迁移时可以将该目录下的数据拷贝到新机器的同个目录下。第一次访问控制台后会生成初始数据。

启动jenkins，直接使用系统服务的启动命令，结果报错，找不到java

$ service jenkins start
Starting Jenkins bash: /usr/bin/java: No such file or directory
                                                           [Failed]

找到/etc/init.d/jenkins文件，在变量candidates后面添加一个路径/usr/java/jdk1.8.0_102/bin/java。

candidates="
/etc/alternatives/java
/usr/lib/jvm/java-1.6.0/bin/java
/usr/lib/jvm/jre-1.6.0/bin/java
/usr/lib/jvm/java-1.7.0/bin/java
/usr/lib/jvm/jre-1.7.0/bin/java
/usr/lib/jvm/java-1.8.0/bin/java
/usr/lib/jvm/jre-1.8.0/bin/java
/usr/bin/java
/usr/java/jdk1.8.0_102/bin/java
"

再启动就成功了

$ service jenkins start
Starting Jenkins                                           [  OK  ]

最后在浏览器访问jenkins，输入：jenkins服务器地址:8888

后续写如何用jenkins实现一键自动部署