Ubuntu VPS部署Django时Gunicorn启动失败的解决方法

问题场景 #

在Hostinger提供的Ubuntu系统VPS上部署Django项目，采用Gunicorn搭配Nginx的架构，持续出现502 Bad Gateway错误，排查发现Gunicorn无法启动。

执行命令查看Gunicorn状态：

sudo systemctl status gunicorn

返回错误信息：

× gunicorn.service - gunicorn daemon
     Loaded: loaded (/etc/systemd/system/gunicorn.service; disabled; vendor preset: enabled)
     Active: failed (Result: exit-code) since Tue 2024-01-02 07:53:47 UTC; 4 days ago
TriggeredBy: ● gunicorn.socket
   Main PID: 6153 (code=exited, status=203/EXEC)
        CPU: 1ms

Jan 02 07:53:47 srv457341 systemd[1]: Started gunicorn daemon.
Jan 02 07:53:47 srv457341 systemd[6153]: gunicorn.service: Failed to execute /root/Assistanza/Assistanza/env/bin/gunicorn: No such file or directory
Jan 02 07:53:47 srv457341 systemd[6153]: gunicorn.service: Failed at step EXEC spawning /root/Assistanza/Assistanza/env/bin/gunicorn: No such file or directory
Jan 02 07:53:47 srv457341 systemd[1]: gunicorn.service: Main process exited, code=exited, status=203/EXEC
Jan 02 07:53:47 srv457341 systemd[1]: gunicorn.service: Failed with result 'exit-code'.
Jan 02 07:53:47 srv457341 systemd[1]: gunicorn.service: Start request repeated too quickly.
Jan 02 07:53:47 srv457341 systemd[1]: gunicorn.service: Failed with result 'exit-code'.
Jan 02 07:53:47 srv457341 systemd[1]: Failed to start gunicorn daemon.

当前Gunicorn服务文件（/etc/systemd/system/gunicorn.service）内容：

[Unit]
Description=gunicorn daemon
Requires=gunicorn.socket
After=network.target

[Service]
User=root
Group=www-data
WorkingDirectory=/root/Assistanza/Assistanza
ExecStart=/root/Assistanza/Assistanza/env/bin/gunicorn \
          --access-logfile - \
          --workers 3 \
          --bind unix:/run/gunicorn.sock \
          Assistanza.wsgi:application

[Install]
WantedBy=multi-user.target

解决步骤 #

问题根源是虚拟环境中Gunicorn未正确安装，按以下步骤修复：

• 删除原有异常的虚拟环境，进入项目根目录：cd /root/Assistanza/Assistanza
• 新建虚拟环境：python3 -m venv new_env（可自定义虚拟环境名称）
• 激活虚拟环境：source new_env/bin/activate
• 重装Gunicorn：pip install gunicorn
• 获取Gunicorn的正确执行路径：which gunicorn，会返回类似/root/Assistanza/Assistanza/new_env/bin/gunicorn的路径
• 编辑Gunicorn服务文件，将ExecStart后的路径替换为上一步得到的正确路径
• 重新加载systemd配置并重启服务：

  sudo systemctl daemon-reload
  sudo systemctl start gunicorn
  

• 再次执行sudo systemctl status gunicorn确认服务启动成功

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