AWS Python Lambda timeout when trying to access MySQL

Question

I'm trying to access our servers MySQL database (Not AWS RDS) with:

def lambda_handler(event, context):
    try:
        conn = pymysql.connect("mySite.com", user="admin", passwd="pass",  connect_timeout=5)

and I'm getting return error:

Response:
{
  "errorMessage": "xxxxxxxxxxxxxxxxxxxxxxxxx Task timed out after 3.00 seconds"
}

I've set up my roles with the AWSLambdaVPCAccessExecutionRole and WSLambdaRole and set up a default VPC network with subnets and security groups:

Security group ID: sg-xxxxxxxx
Ports: All
Destination: 0.0.0.0/0

Is there something I'm forgetting? I tested this with a RDS and I'm able to connect to the DB it's just when I try an external DB it's timing out.

Mark B · Accepted Answer · 2019-09-18 19:29:40Z

2

If the database isn't in the VPC, then the Lambda function won't have access to it. When you run a Lambda function inside a VPC the Lambda function is not assigned a public IP address. To give it access to resources outside the VPC the Lambda function will have to be in a private subnet, with a route to a NAT Gateway.

Alternatively, if it does not need to access resources inside the VPC, then just remove it from the VPC and it will have Internet access.

If the database is in the VPC running on an EC2 server, then you probably need to open the security group assigned to the EC2 server appropriately.

answered Sep 18, 2019 at 19:29

Mark B

203k27 gold badges339 silver badges332 bronze badges

Sign up to request clarification or add additional context in comments.

7 Comments

i73 Over a year ago

I originally was running without the VPC, but to test with the RDS I added one, I'm still getting the timeout error after removing the VPC. Any other ideas? I don't need access to a RDS I need access to a remote DB.

Mark B Over a year ago

Is your database server actually accessible from the Internet? At this point it sounds like a networking issue on the database end.

i73 Over a year ago

Hey Mark, sorry I've been caught up. I'm able to access the server through SSH with a public/private key so I don't think it's not accessible, and I would have assumed this would just throw up a connection error if the credentials are not found or missing, so can you suggest anything else?

Mark B Over a year ago

Accessing the server through SSH doesn't mean the firewall(s) in front of the server allow direct connections to the database. You need to test connecting to the database from the Internet, like via some software on your laptop, to verify it is accessible.

Georgi Ivanov Dimitrov Over a year ago

I have the same problem here.I am in the staging VPC with all subnets, and I am in the staging security group. Still I can not get access, and I am not getting any error messages just timing out.

|

Collectives™ on Stack Overflow

AWS Python Lambda timeout when trying to access MySQL

1 Answer 1

7 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

7 Comments

Your Answer

Sign up or log in

Post as a guest

Related