How to configure the mail service-Qoder CN Series(Lingma)-阿里云帮助中心

This topic describes how to configure a mail server and test its connectivity.

Applicable editions

Enterprise Dedicated

Configure the mail server

Enterprise administrators can configure the SMTP mail service for sending notifications under Global Configuration > Mail Service. The configuration takes effect about 5 minutes after you save it.

Use the switch to enable or disable the mail service.
The sender email address, SMTP server domain name, and SMTP server port fields are required.
The SMTP username and SMTP password fields are optional.

You can also configure other settings, such as Server has TLS enabled, the Clients Skip TLS Verification checkbox, and the SMTP Authentication Method. For the authentication method, PLAIN is available but not recommended due to its low security. After you complete the configuration, enter a recipient email address in the connectivity test area at the bottom of the page and click Test to verify that the mail service is working.

Test connectivity

After you complete the configuration, enter a recipient email address to test the connectivity.

If the test fails, refer to the following table for common SMTP configuration errors.

Error message	Issue
dial tcp: lookup XXX: no such host	DNS resolution failed for the SMTP server domain name.
526 Authentication failure[0]	Invalid username or password.
dial tcp XXX:XX: connect: operation timed out	Network unreachable or incorrect port.
x509: certificate signed by unknown authority	TLS certificate verification for the SMTP server failed. This is typically caused by a self-signed certificate. To resolve this issue, replace the certificate with a CA-issued certificate, or configure the TLS port and select the "Clients Skip TLS Verification" checkbox. Note: If STARTTLS is configured on a non-TLS port, the connection is upgraded to TLS, and the verification cannot be skipped.
tls: first record does not look like a TLS handshake	The configured port is not a TLS port.
550 Mail is rejected by recipients	The email was rejected by the recipient's mail service. Contact the recipient's mail service provider to resolve the issue.
554 5.7.1 Too many spam complaints	The email was rejected by the recipient's mail service. Contact the recipient's mail service provider to adjust the inbound email rate limit.
501 Bad address syntax	Invalid recipient email address.
427 Socks Connect to UNREACHABLE host	The destination host is unreachable. This typically occurs when the MX record for the recipient's domain is missing. Ask the recipient to verify the MX record for their domain.

Click Save. It takes about 5 minutes for the changes to take effect.