AWS Lambda Function how to to Access RDS Instance with VPC Configuration
Quick question that's been bugging me - I'm currently working with an scenario where my AWS Lambda function, which is configured to run in a VPC, is unable to connect to my Amazon RDS PostgreSQL instance. Both resources are in the same VPC and I have set up the necessary security groups. However, I'm receiving a `ConnectionTimeout` behavior when the Lambda function tries to execute the database query. Here's the relevant portion of my Lambda function's code: ```python import psycopg2 import os def lambda_handler(event, context): try: conn = psycopg2.connect( dbname=os.environ['DB_NAME'], user=os.environ['DB_USER'], password=os.environ['DB_PASSWORD'], host=os.environ['DB_HOST'], port=os.environ['DB_PORT'] ) cursor = conn.cursor() # Execute a simple query cursor.execute('SELECT 1;') result = cursor.fetchone() return result except Exception as e: return str(e) ``` I've also configured the security group attached to the RDS instance to allow inbound traffic on port 5432 from the Lambda function's security group. Here's how I set it up: - RDS Security Group: - Inbound Rule: Type: PostgreSQL, Source: Lambda Security Group (sg-xxxxx) Additionally, I made sure the Lambda execution role has the necessary permissions to access the resources in the VPC. The execution role policy looks like this: ```json { "Version": "2012-10-17", "Statement": [ { "Effect": "Allow", "Action": [ "logs:CreateLogGroup", "logs:CreateLogStream", "logs:PutLogEvents" ], "Resource": "*" }, { "Effect": "Allow", "Action": "ec2:DescribeNetworkInterfaces", "Resource": "*" } ] } ``` Despite these configurations, the Lambda function still times out after 30 seconds. I've tried increasing the timeout setting in the Lambda console, but that didn't help. I even checked the VPC settings to ensure that the subnet has a route to the internet, but since this is a database connection, I'm not sure that's necessary. Has anyone else faced similar issues connecting a Lambda function to an RDS instance in a VPC? What could I be missing in my configuration? I'm developing on Windows 11 with Python. I appreciate any insights! Is this even possible?