Jenkins fails on sending emails - email

Question

I'm trying to send email from Jenkins using Extended Jenkins Email plugin.
Here is the output of the job:
Performing post-build step
Checking if email needs to be generated
Email was triggered for: Always
Email was triggered for: Always
Sending email for trigger: Always
messageContentType = text/plain; charset=UTF-8
Adding recipients from project recipient list
Adding recipients from trigger recipient list
Setting In-Reply-To since last build was not successful
Successfully created MimeMessage
Sending email to: tomasz.szandala#nokia.com
DEBUG: getProvider() returning javax.mail.Provider[TRANSPORT,smtp,com.sun.mail.smtp.SMTPTransport,Sun Microsystems, Inc]
DEBUG SMTP: useEhlo true, useAuth true
DEBUG SMTP: useEhlo true, useAuth true
DEBUG SMTP: trying to connect to host "webmail-apac.nsn-intra.net", port 465, isSSL false
MessagingException message: Could not connect to SMTP host: webmail-apac.nsn-intra.net, port: 465
Sending email for trigger: Always
messageContentType = text/plain; charset=UTF-8
Adding recipients from project recipient list
Adding recipients from trigger recipient list
Setting In-Reply-To since last build was not successful
No, the question: how can I check wht is the problem?
I see only:
MessagingException message:
"Could not connect to SMTP host: webmail-apac.nsn-intra.net, port: 465"
How can I investigate the reason?

Answer 1

I think it's a network issue, your Jenkins server is not able to reach your SMTP server on the port 465.
Can you launch the following command to check if the port is open? (on your Jenkins server, with the jenkins account running the Jenkins app)
telnet webmail-apac.nsn-intra.net 465
If the port is open, you should see this response:
➜ ~ webmail-apac.nsn-intra.net 465
Trying XXX.XXX.XXX.XXX...
Connected to webmail-apac.nsn-intra.net.
Escape character is '^]'.
If the port is not open, try to disable the firewall on your Jenkins server.