AWS EC2 Linux服务器Jenkins启动失败问题求助

环境与已执行操作 #

• 已安装Java 1.8.0-openjdk，配置环境变量：

  JAVA_HOME=/usr/lib/jvm/java-1.8.0-openjdk-1.8.0.342.b07-1.amzn2.0.1.x86_64
  PATH=$PATH:$HOME/bin:$JAVA_HOME:$MAVEN_HOME:$M2
  

• 按官方步骤安装Jenkins，执行命令：

  sudo wget -O /etc/yum.repos.d/jenkins.repo \
      https://pkg.jenkins.io/redhat/jenkins.repo
  sudo rpm --import https://pkg.jenkins.io/redhat/jenkins.io.key
  sudo yum upgrade
  # 安装Jenkins依赖
  sudo yum install jenkins
  sudo systemctl start jenkins
  

• 已确认未安装Tomcat，8080端口应可用；并在/etc/init.d/jenkins的candidates项中指定Java路径：

  candidates="/usr/lib/jvm/java-1.8.0-openjdk-1.8.0.342.b07-1.amzn2.0.1.x86_64/bin/java"
  

错误信息 #

• 执行systemctl start jenkins后提示：

  Job for jenkins.service failed because the control process exited with error code. See "systemctl status jenkins.service" and "journalctl -xe" for details.
  

• 执行systemctl status jenkins.service输出：

  jenkins.service - Jenkins Continuous Integration Server
     Loaded: loaded (/usr/lib/systemd/system/jenkins.service; enabled; vendor preset: disabled)
     Active: failed (Result: start-limit) since Wed 2022-12-21 10:15:02 UTC; 10s ago
    Process: 20467 ExecStart=/usr/bin/jenkins (code=exited, status=1/FAILURE)
   Main PID: 20467 (code=exited, status=1/FAILURE)
  Unit jenkins.service entered failed state.
  jenkins.service failed.
   jenkins.service holdoff time over, scheduling restart.
   Stopped Jenkins Continuous Integration Server.
  start request repeated too quickly for jenkins.service
  Failed to start Jenkins Continuous Integration Server.
  Unit jenkins.service entered failed state.
  jenkins.service failed. 
  

解决方案 #

1. 修正systemd服务的Java路径配置 #

Amazon Linux 2使用systemd管理服务，修改/etc/init.d/jenkins不会生效，需直接编辑systemd配置文件：

sudo vi /usr/lib/systemd/system/jenkins.service

找到Environment="JAVA_HOME=..."行，替换为你的Java路径：

Environment="JAVA_HOME=/usr/lib/jvm/java-1.8.0-openjdk-1.8.0.342.b07-1.amzn2.0.1.x86_64"

保存后重载systemd配置并重启服务：

sudo systemctl daemon-reload
sudo systemctl restart jenkins

2. 验证Java路径有效性 #

确认Java可执行文件存在且具备执行权限：

ls -l /usr/lib/jvm/java-1.8.0-openjdk-1.8.0.342.b07-1.amzn2.0.1.x86_64/bin/java
/usr/lib/jvm/java-1.8.0-openjdk-1.8.0.342.b07-1.amzn2.0.1.x86_64/bin/java -version

若路径错误，执行alternatives --config java查看系统可用Java版本，选择正确路径更新配置。

3. 查看Jenkins详细启动日志 #

通过日志定位具体故障原因：

# 实时查看Jenkins服务日志
sudo journalctl -u jenkins.service -f
# 查看本地日志文件
sudo cat /var/log/jenkins/jenkins.log

常见问题包括Jenkins用户对日志/数据目录无读写权限、端口被占用等。

4. 检查端口占用情况 #

确认8080端口是否被其他进程占用：

sudo netstat -tulpn | grep 8080

若端口被占用，修改Jenkins配置文件/etc/sysconfig/jenkins中的JENKINS_PORT为其他端口（如8081），再重启服务：

sudo vi /etc/sysconfig/jenkins
# 修改JENKINS_PORT="8081"
sudo systemctl restart jenkins

5. 修复Jenkins目录权限 #

若日志提示权限不足，执行以下命令修复：

sudo chown -R jenkins:jenkins /var/lib/jenkins
sudo chown -R jenkins:jenkins /var/log/jenkins
sudo chown -R jenkins:jenkins /var/cache/jenkins

内容的提问来源于stack exchange，提问作者Goutham