aws rds proxy throws timeout error from nodejs12.x

Question

I'm getting a connection timeout when I try to connect to mysql rds proxy. I'm followed this tutorial

This is my code

import mysql2 from 'mysql2';
import AWS from 'aws-sdk';
const getConnection = async () => {
    const signer = new AWS.RDS.Signer({
        username: 'my-user-name',
        hostname: 'proxy-name.proxy-someid.us-east-1.rds.amazonaws.com',
        port: 3306
    });

    console.info('Connecting to MySQL proxy via IAM authentication');

    const rdsSignerAuth = () => () => {
        console.info('CALL rdsSignerAuth');
        return signer.getAuthToken({
            username: 'my-user-name',
            region: 'us-east-1',
            hostname: 'proxy-name.proxy-someid.us-east-1.rds.amazonaws.com',
            port: 3306
        });
    };

    let connection;
    try {
        connection = await mysql2.createConnection({
            host: 'proxy-name.proxy-someid.us-east-1.rds.amazonaws.com',
            user: 'my-user-name',
            database: 'database-name',
            connectTimeout: 60000,
            ssl: { rejectUnauthorized: false },
            authPlugins: { mysql_clear_password: rdsSignerAuth },
        });
        console.info('Connected');
    }
    catch (e) {
        console.error(`MySQL connection error: ${e}`);
        throw e;
    }
    return connection;
};
const mysql2Impl = async () => {
    const connection = await getConnection();
    //console.info({ type: 'connection', connection });
    const result = await connection.promise().query('select * from destiny;');
    console.info({ type: 'result', result });
};
export async function testRdsProxy(event, context){
    console.info(JSON.stringify({ event, context }));
    await mysql2Impl();
    return 200;
}

And this is the response

Error {
    code: 'ETIMEDOUT',
    errno: undefined,
    message: 'connect ETIMEDOUT',
    sqlState: undefined,
  }

I already checked that my lambda function has a policy "rds-db:connect" to "*" resource. Besides, I checked that my proxy is in the same VPC and subnet that my rds db. The secret that holds the credentials to RDS is ok. What I am doing wrong?

Answer 1

The doc states that the RDS proxy cannot be accessed public, so your lambda function need to be in the same security group with the rds proxy. Please aware that when you make your lambda into a vpc, your lambda may lost its ability to access internet. Thank you.