PM2

Installing PM2 Globally

To install PM2 globally, use npm:

sudo npm install -g pm2

Using PM2 to Start Applications

Starting a Node.js Application

To start a Node.js application with PM2, navigate to your application directory and use the following command:

pm2 start /path/to/your/app.js --name your-app-name

For example:

pm2 start /home/ubuntu/my-node-app/index.js --name my-node-app

Starting a Python Application

To start a Python application with PM2, use the following command:

pm2 start /path/to/your/app.py --interpreter python3 --name your-python-app

For example:

pm2 start /home/ubuntu/my-python-app/app.py --interpreter python3 --name my-python-app

注意：如果使用了Python虚拟环境，要注意路径

Setting Up PM2 Startup Script

To set up PM2 to start on system boot:

pm2 startup

This command will generate a command specific to your operating system. Run the generated command to complete the setup.

Saving the PM2 Process List

To save the list of processes so they restart automatically on reboot:

pm2 save

Managing Applications with PM2

Listing Running Processes

To list all running processes managed by PM2, use:

pm2 list

Stopping a Process

To stop a process, use the process name or ID:

pm2 stop your-app-name
# or
pm2 stop <process-id>

Restarting a Process

To restart a process, use:

pm2 restart your-app-name
# or
pm2 restart <process-id>

Deleting a Process

To delete a process, use:

pm2 delete your-app-name
# or
pm2 delete <process-id>

Viewing Logs

To view logs for all processes:

pm2 logs

To view logs for a specific process:

pm2 logs your-app-name
# or
pm2 logs <process-id>

PM2 Common Commands

Reloading PM2 Configuration

To reload PM2 configuration without downtime (useful for zero-downtime restarts):

pm2 reload all

Viewing Process Details

To view detailed information about a specific process:

pm2 describe your-app-name
# or
pm2 describe <process-id>

Monitoring Resource Usage

To monitor resource usage (CPU, Memory) of your processes:

pm2 monit

Add airflow to EC2 service via PM2

start_airflow.sh

#!/bin/bash
 
# 设置 AIRFLOW_HOME
export AIRFLOW_HOME=/home/ubuntu/Data-collection-service
 
# 激活虚拟环境
source /home/ubuntu/Data-collection-service/airflow_env/bin/activate
 
# 停止所有正在运行的 Airflow 服务
pkill -f "airflow webserver"
pkill -f "airflow scheduler"
pkill -f "airflow worker"
 
# 确保所有进程已停止
sleep 5
 
# 再次确认是否有残留进程
PIDS=$(ps -ef | grep "airflow" | grep -v grep | awk '{print $2}')
if [ -n "$PIDS" ]; then
  echo "Killing remaining Airflow processes..."
  kill -9 $PIDS
fi
 
# 启动 Airflow webserver
airflow webserver --port 8080 &
 
# 启动 Airflow scheduler
airflow scheduler &
 

chmod +x start_airflow.sh
pm2 start start_airflow.sh --name airflow
pm2 startup
pm2 save
pm2 status