Connecting KNIME Hub to On-Premises Databases: Troubleshooting IP Whitelisting

Hi everyone,

I am currently working on connecting our KNIME Hub environment to our on-premises databases (which are naturally not exposed to the public internet).

I have been following the Hub User Guide, and so far, I have:

  1. Requested and received the dedicated IP from the KNIME team.

  2. Whitelisted this specific KNIME Hub IP on our firewall.

  3. Opened the custom database port on our public-facing IP to route traffic to the internal server.

Despite this setup, I am still unable to establish a connection. Has anyone in the community successfully implemented this direct connection approach?

Specifically, I am wondering:

  • Are there any hidden requirements, additional ports, or specific protocols that need to be allowed on the firewall besides the primary DB port?

  • Did any of you end up using a different architecture, such as an SSH tunnel or a reverse proxy, to solve this?

Any guidance, architecture tips, or shared experiences would be highly appreciated!

Thanks in advance!