Unable to connect to Postgres, throws error

Thanks for MFelix's concern about this issue.

Hi, Cesylyaa 

I am glad to help you.

The error message “No such host is known” usually means that the host name cannot be resolved.

The first thing you can do is to check the spelling of the hostname to make sure that it is not misspelled.

You can also check to see if your machine can resolve the hostname. You can use the ping command in your terminal:

ping cbdh854d5.cluster-czrsj4isg7.us-east-1.rds.amazonaws.com

You also need to make sure that port 5432 is open and not blocked by a firewall.

I hope my suggestions give you good ideas, if you have any more questions, please clarify in a follow-up reply.
Best Regards,
Fen Ling,
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