When testing, or using, the CDD SMTP Plugin it returns:
'UNKNOWN' Failure. Unable to Send Test Message to '[email protected]'
When reviewing Tomcat's catalina.out file we can see the following errors:
SMTP Servers/Relays (or proxies in between) can be setup so that attempts to send mail via, typically insecure, port 25 are converted in the background to use SSL. Java applications will raise these exceptions when it does not have a copy of the certificate (or it's root/intermediate). This is needed for the SSL Handshake to complete successfully.
SMTP Plugin Option: Use secure communication = not in use
Component : Continuous Delivery Director
Add the needed certificates to the java used by the SMTP Plugin. Do this by running the command:
/path/to/keytool -importcert -alias smtpCert -file <new certificate file> -kestore /path/to/java's/lib/security/cacerts
Note: See the "Additional Information" section below for more details on how to debug (identify/confirm truststore being used, certificate chain received, certificates in truststore, etc..).
SSL Debug can be enabled by updating the appropriate Tomcat startup file to include the following java argument: -Djavax.net.debug=all
Afterwards you can find the debug output in the catalina.out file. In the debug output you can look for relevant information in the sections:
Links where additional information is available: