Connection failing for AWS Redshift Serverless in Redash

[nikhilbabaria07]

Description:

I'm trying to add a data source for AWS Redshift Serverless in Redash.

As per the documentation, I also whitelisted the Redash server IP address for the required port(5439) within the SecurityGroup of the Redshift cluster.

Actual Behavior:

When testing the connection to the cluster from Redash, I get the following error:
could not send SSL negotiation packet: Resource temporarily unavailable

I'm encountering the same error when 'SSL Mode' is kept empty and when it is set to prefer.

Expected Behavior:

The connection to the data source should be established successfully.

Additional Context:

I referred to the following Redash documentation to implement the same: https://redash.io/help/data-sources/querying/amazon-redshift

What could be the problem and how can I solve it?