AWS DMS Failed Connection to On-Premises MySQL as Source DB

Question

I am currently involved in a scenario where I need to migrate my client's on-premises MySQL database data to AWS DynamoDB tables. To accomplish this task, I have set up a successful connection for the DynamoDB table (target) using AWS DMS.

However, I'm facing an issue when trying to connect to the on-premises database. The test endpoint connection always fails, and the error message indicates the problem. Interestingly, I can connect to the on-premises database through MySQL Workbench using the same set of credentials that I used for the endpoint.

To address this problem, I have already taken some steps. I created a route table and allowed traffic from the internet to the replication instance. Despite these efforts, the issue persists. If anyone has any suggestions or insights on how to resolve this, I would greatly appreciate your help.

Error Message :
*Test Endpoint failed: Application-Status: 1020912, Application-Message: Cannot connect to ODBC provider ODBC general error., Application-Detailed-Message: RetCode: SQL_ERROR SqlState: HY000 NativeError: 2003 Message: [MySQL][ODBC 8.0(w) Driver]Can't connect to MySQL server on 'SERVER IP ADDRESS' (111)*

I also referred the below article (Configuration for a network to a VPC using the Internet)
https://docs.aws.amazon.com/dms/latest/userguide/CHAP_ReplicationInstance.VPC.html

Thank you in advance.

Gary Mclean · Answer

Correct me if I am wrong, surely If you’re wanting to connect to an On premises SQL server you will be targeting a RFC1918 ip addresses?

Not 100% sure why you would want to route via the internet for anything?

Does the host start with 10 or 172 or 192 ?

Do you have DX or VPN setup?

Swathi P · Answer

Please check or configure on-premise firewall so that on-premise MySQL allows connections from AWS DMS. The CIDR range of your private subnet where replication instance is created must be configured in on-premise firewall.

The route table need not be configured to allow traffic from internet for replication instance.

Paul · Answer

I'm having the same problem. I've had the replication instance (EC2) public IP address whitelisted by my current hosting provider. I've verified the username/password/port/address are all valid. What security settings might I be missing to get the source to connect properly?

Do I need to have him whitelist the private IP address/range even though this is being done across the public interface?

AWS DMS Failed Connection to On-Premises MySQL as Source DB

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