I am writing this proposal to provide solutions and support for your Docker and Postfix-hosted websites having difficulty sending email from a specific Docker container.
I understand that this container was working fine on your old server, but on your new server, it is not functioning properly. After reviewing the issue, I have identified a few potential solutions for this problem.
First, I recommend that you review the configuration files in the Docker container and make sure they are up-to-date and accurate. I would also suggest that you check the security settings on your new server to make sure that they are allowing outbound connections from the Docker container.
Next, I will review the Postfix configuration and logs to see if there is a problem with the mail server settings. I can also use Postfix commands to test the mail server’s ability to send emails from the Docker container, which should help isolate the issue.
Finally, I can investigate any existing security measures on your server to make sure they are not blocking outbound emails from the Docker container.
I have extensive experience with Linux servers, Postfix, and Docker, and I am confident that I can help you resolve this issue.