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Verify SMTP server SSL / TLS certificate

Do you wanna verify the configuration for your certificate in your SMTP server? It’s as easy as this:

openssl s_client -connect -starttls smtp -CApath /etc/ssl/certs

Substitute ‘’ with your server.

The route for your root certificates (/etc/ssl/certs), which is necessary for verifying them, might vary depending on your linux distro. That route should be fine for debian and ubuntu based distros.