KNIME Server Email Notification Setup Process

Hello All,

We are currently in the process of setting up email notifications on our KNIME server, as outlined in the documentation at the following link: KNIME Server Email Notification Guide.

Despite configuring the mail.smtp.host on the KNIME server, we have not been receiving any email notifications. We are uncertain about what might be missing in the configuration. Could someone please assist us in understanding the steps to properly set up email notifications for workflows on the KNIME server?

Thank you for your support.

Configuration:

Error Logs:

@kotlapullareddy The error you are getting indicates that the connection to your email server is timing out. This could be due to a number of reasons. Most commonly it’s due to misconfiguration, network restrictions or routing issues, or not adhering to the email servers requirements to relay mail.

I would start by checking to ensure the fully qualified domain name (fqdn) for your mail server is correct and resolves appropriately via DNS query. Once confirmed make sure that the mail.smtp.host setting matches the confirmed fqdn.

You will also need to confirm what port your email server is using for smtp services. Port 25 is the default, but ports 465 and 587 are also common. Especially if the email server requires a secure connection. If your email server uses a port other than 25 you will need to set the ‘mail.smtp.port’ setting to the appropriate value. If your email server requires a secure connection you will also need to set either ‘mail.smtp.starttls.enable’ or ‘mail.smtp.ssl.enable’ to true as both settings default to false.

All email servers require a from address to relay mail. As such you should also set the ‘mail.smtp.from’ to a valid email address that is allowed to relay mail. I usually recommend that this be a service account rather than an individual user.

Your email server may also require authentication in order to relay mail. If so you will need to set the ‘mail.smtp.auth’ setting to true and provide the credentials for the email user via the ‘mail.smtp.user’ and ‘mail.password’ settings. These settings are optional and would only be needed if your email server requires authentication.

If you are still having issues after confirming all of the settings are properly configured for your email server I would do some testing outside of KNIME to ensure the machine hosting KNIME Server can communicate with your email server and relay mail. This can be done with simple tools like telnet or sendmail. The following article is an excellent start for further troubleshooting smtp issues.

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