centos7 安装jenkins

1.添加数据源
sudo wget -O /etc/yum.repos.d/jenkins.repo https://pkg.jenkins.io/redhat-stable/jenkins.repo
sudo rpm --import https://pkg.jenkins.io/redhat-stable/jenkins.io.key
2.yum install jenkins
3.启动报如下错误
Starting Jenkins bash: /usr/bin/Java: No such file or directory
4.修改 vim /etc/init.d/jenkins
在candidates中第一行添加java路径，如下：
candidates="
/opt/soft/jdk1.8.0_60/bin/java
/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
"
5.修改端口号和用户
vi /etc/sysconfig/jenkins
JENKINS_USER="root"
JENKINS_PORT="20000"
6.firewall-cmd --zone=public --add-port=20000/tcp --permanent
firewall-cmd --reload
7.如果服务器是阿里云服务器需要去安全组策略开放端口
8.启动服务 service jenkins start