topic Re: Cluster Access mode set to Shared on Databricks, results in connection refused on Exasol in Get Started Discussions

Cluster Access mode set to Shared on Databricks, results in connection refused on Exasol

Gembo — Tue, 05 Dec 2023 16:05:47 GMT

I am trying to run a TRUNCATE command on my exasol DWH from Databricks using the pyexasol. This works perfectly fine when I have the cluster access mode as "No Isolation Shared" which does not have access to our Unity Catalog. When I change the cluster access mode to "Shared" and now has access to Unity Catalog, the cluster fails to connect to Exasol DWH with the following error message:

"Could not connect to Exasol: [Errno 111] Connection refused"

Any ideas how to solve this?

Re: Cluster Access mode set to Shared on Databricks, results in connection refused on Exasol

SSundaram — Tue, 05 Dec 2023 22:28:57 GMT

Interesting. Did you try with "Single User" mode, which also has UC support?

Re: Cluster Access mode set to Shared on Databricks, results in connection refused on Exasol

Gembo — Wed, 06 Dec 2023 09:06:38 GMT

@SSundaram "Single user" access mode works when connecting using pyexasol, but this cluster is being accessed by our whole Data Engineering team and would not really be a viable solution.

Re: Cluster Access mode set to Shared on Databricks, results in connection refused on Exasol

Gembo — Wed, 06 Dec 2023 09:09:08 GMT

It is not a problem of connectivity/firewall as I am able to connect using pyexasol when setting the access mode to different values on Databricks Cluster. Our Exasol and Databricks are not trial modes as these are our main DWH/Data Lakehouse for our data.

Re: Cluster Access mode set to Shared on Databricks, results in connection refused on Exasol

SSundaram — Wed, 06 Dec 2023 15:49:35 GMT

Understood. So UC is not the problem, but the access mode is what causing this issue. There are few limitations with shared access mode on UC. I am guessing it might be the credentials passthrough, not sure.