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587

SMTP Submit

Email message submission

TCP
Email

Port Information

Port Number

587

Protocol

TCP

Category

Email

Common Usage

URL with Port

http://localhost:587
https://example.com:587

Node.js/Express Server

const express = require('express');
const app = express();
const PORT = 587;

app.listen(PORT, () => {
  console.log(`Server running on port ${PORT}`);
});

Docker Port Mapping

docker run -p 587:587 myapp

# In docker-compose.yml
ports:
  - "587:587"

Firewall Configuration

# Linux/Ubuntu firewall
sudo ufw allow 587/tcp

# Check if port is in use
netstat -an | grep 587