Ubuntu中通过SSM文档运行Systemd服务时无法访问Jar文件

问题背景 #

通过AWS SSM文档将Spring PetClinic部署至Ubuntu 22服务器，服务启动后反复失败，执行sudo journalctl -u spring-petclinic.service返回找不到jar文件的错误，尝试权限配置、以root用户运行均未解决。

错误日志 #

May 17 21:52:36 ip-10-0-4-141 systemd[1]: spring-petclinic.service: Failed with result 'exit-code'.
May 17 21:52:36 ip-10-0-4-141 systemd[1]: spring-petclinic.service: Scheduled restart job, restart counter is at 3.
May 17 21:52:36 ip-10-0-4-141 systemd[1]: Stopped Spring PetClinic Application.
May 17 21:52:36 ip-10-0-4-141 systemd[1]: Started Spring PetClinic Application.
May 17 21:52:36 ip-10-0-4-141 java[7076]: Error: Unable to access jarfile /clinic/spring-petclinic/target/*.jar
May 17 21:52:36 ip-10-0-4-141 systemd[1]: spring-petclinic.service: Main process exited, code=exited, status=1/FAILURE
May 17 21:52:36 ip-10-0-4-141 systemd[1]: spring-petclinic.service: Failed with result 'exit-code'.
May 17 21:52:36 ip-10-0-4-141 systemd[1]: spring-petclinic.service: Scheduled restart job, restart counter is at 4.
May 17 21:52:36 ip-10-0-4-141 systemd[1]: Stopped Spring PetClinic Application.
May 17 21:52:36 ip-10-0-4-141 systemd[1]: Started Spring PetClinic Application.
May 17 21:52:36 ip-10-0-4-141 java[7077]: Error: Unable to access jarfile /clinic/spring-petclinic/target/*.jar
May 17 21:52:36 ip-10-0-4-141 systemd[1]: spring-petclinic.service: Main process exited, code=exited, status=1/FA

故障根源分析 #

查看提供的SSM运行文档，核心问题出在CreateSystemdService步骤：

1. systemd服务文件格式错误：生成spring-petclinic.service时，[Unit]区块内混入了echo命令，导致systemd无法正确解析服务配置。
2. 通配符未被解析：ExecStart中的*.jar通配符不会被systemd自动解析，必须通过shell处理。
3. 冗余操作：重复清空并重置/etc/environment属于不必要操作，可能导致环境变量异常。

修复步骤 #

1. 修正SSM文档的CreateSystemdService步骤 #

替换原脚本内容，确保生成合法的systemd服务文件，并通过shell解析通配符：

---
schemaVersion: '2.2'
description: Install Java 17 and run the Spring PetClinic application
parameters: {}
mainSteps:
# 保留InstallJava17和DownloadApplication步骤不变，仅修改CreateSystemdService
- name: CreateSystemdService
  action: aws:runShellScript
  inputs:
    runCommand:
    - |
      #!/bin/bash
      
      # 确保JAVA_HOME环境变量正确
      JAVA_HOME=$(sudo update-alternatives --config java | grep -o -E '/usr/lib/jvm/[a-zA-Z0-9-]+') 
      echo "JAVA_HOME=\"$JAVA_HOME\"" | sudo tee -a /etc/environment
      
      # 生成合法的systemd服务文件
      sudo tee /etc/systemd/system/spring-petclinic.service <<EOF
      [Unit]
      Description=Spring PetClinic Application
      After=network.target
      
      [Service]
      # 使用shell解析通配符，确保找到正确的jar文件
      ExecStart=/bin/sh -c "$JAVA_HOME/bin/java -jar /clinic/spring-petclinic/target/*.jar"
      Restart=always
      User=root
      # 设置工作目录，避免路径问题
      WorkingDirectory=/clinic/spring-petclinic
      
      [Install]
      WantedBy=multi-user.target
      EOF
      
      # 重新加载systemd配置并启动服务
      sudo systemctl daemon-reload
      sudo systemctl enable spring-petclinic
      sudo systemctl start spring-petclinic

2. 验证jar文件生成（可选） #

在DownloadApplication步骤中添加构建校验，确保Maven构建成功生成jar：

# 在./mvnw package后添加以下内容
if [ ! -f target/*.jar ]; then
  echo "Maven构建失败，未生成jar文件"
  exit 1
fi

验证修复效果 #

1. 检查生成的服务文件是否合法：

cat /etc/systemd/system/spring-petclinic.service

确保文件中无多余echo命令，ExecStart格式正确。

2. 启动服务并查看状态：

sudo systemctl start spring-petclinic
sudo systemctl status spring-petclinic

3. 实时查看服务日志：

sudo journalctl -u spring-petclinic.service -f

内容的提问来源于stack exchange，提问作者SovietFrontier