Lambda timeout accessing redshift

Question

I am trying to connect to Redshift cluster via python lambda function. I've checked the following for the lambda:

• Role for lambda
  • AmazonRedshiftFullAccess
  • AWSLambdaVPCAccessExecutionRole
• VPC enabled for lambda
  • Inbound (Protocol = All, Ports = All, source = SG1)
  • Outbound (Protocol = All, Ports = All, destination = 0.0.0.0/0)

For the redshift cluster, it is in the same VPC as lambda and not publicly accessible. So in the lambda environment, I had used the redshift private IP.

However, when I try running the lambda, it timeout after the x seconds still.

Answer 1

The security configuration should be:

• The AWS Lambda function should be connected to the same VPC as the Amazon Redshift cluster
• A Security Group on the AWS Lambda function (Lambda-SG) that has the default "Allow All" rules for Outbound connections
• A Security Group on the Redshift database (Redshift-SG) that permits Inbound connections on port 5439 from Lambda-SG

That is, the Redshift-SG should specifically reference the Lambda-SG (by sg- ID) in the Inbound rule. This will permit the Lambda function to communicate with the Redshift database.