Linux：systemd和systemctl基本使用示例

(目录)

文档

• https://www.freedesktop.org/software/systemd/man/latest/systemd.unit.html
• Systemd 入门教程：命令篇
• Systemd 入门教程：实战篇

systemd管理Flask应用示例

创建虚拟环境，做好环境隔离

# Python2.7 使用virtualenv创建虚拟环境
$ pip install virtualenv
$ virtualenv venv
$ source ./venv/bin/activate  # 进入虚拟环境激活 

# Python3+ 使用venv模块创建虚拟环境

app.py

# 安装依赖：pip install flask
from flask import Flask

app = Flask(__name__)

@app.route('/')
def index():
    return "Hello world"

if __name__ == "__main__":
    app.run(host='0.0.0.0', port=80)

添加 flask-app.service

# /usr/lib/systemd/system/flask-app.service
[Unit]
Description=Flask App

[Service]
ExecStart=/opt/flask-app/venv/bin/python /opt/flask-app/app.py
Restart=always

[Install]
WantedBy=multi-user.target

需要注意：启动命令要用绝对路径

systemctl常用操作

# 设置开机启动
systemctl enable flask-app

# 检查开机启动
systemctl is-enabled flask-app

# 启动应用
systemctl start flask-app

# 查看应用状态
systemctl status flask-app

# 重启服务
systemctl restart flask-app

# 重新加载配置文件
$ systemctl daemon-reload

# 查看日志
journalctl -u flask-app -f