If you use a Hive Linked Service in your Azure Synapse workspace, you have probably been getting a banner at the top of your workspace every time you sign in telling you that you have linked services that are about to be deprecated so you should update them. If, like me, you go ahead and do that upgrade from version 1.0 to version 2.0, which is touted as being as simple as toggling a switch, you may have been disappointed to find that you now have an error with your connector that prevents your pipelines from running. If this is relatable to you, keep reading because I will tell you how you can resolve the issue.
Fortunately or unfortunately, depending on how you look at it, I was a preview tester for Microsoft for the fix to the Hive V2.0 connector issue because the problem had already been reported and had a fix in progress when I created a ticket with Microsoft support. The solution has now been released and is available for you to implement if you need it.
What’s in this Post
The Problem with the Hive 2.0 Connector
For a couple months, my team was being annoyed with a banner every time we opened one of our workspaces which utilizes a Hive linked service, telling us that we have a linked service version that is going to be deprecated soon. In August, I finally decided I had enough of the banner and decided to do the requested upgrade to our Hive Linked Service, to upgrade to version 2.0. Making the change was simple enough, changing the radio button we had selected in the settings of the linked service (LS), and I didn’t even have to fix any settings of the LS after making the switch like I had to do with an upgrade to our Oracle connectors. All previously saved settings stayed where they were, so I saved the change and merged it.
A couple days later, on the next run of our pipeline that uses that linked service, we got the following error on the “Copy Data” activity which pulls data from the Hive data source into our data lake.
"ErrorCode=FailedToConnectMSDISource,'Type=Microsoft.DataTransfer.Common.Shared.HybridDeliveryException,Message=Failed to connect to the connector. Error code: 'AuthenticationError', message: 'One or more errors occurred., ErrorCode: AuthenticationError',Source=Microsoft.DataTransfer.Connectors.MSDIBridgeAdapter,''Type=Microsoft.DI.Driver.Hive.Exceptions.HiveConnectorException,Message=One or more errors occurred., ErrorCode: AuthenticationError,Source=Microsoft.DI.Driver.Hive,''Type=Apache.Arrow.Adbc.Drivers.Apache.Hive2.HiveServer2Exception,Message=An unexpected error occurred while opening the session. 'Required field 'client_protocol' was not present! Struct: TOpenSessionReq(client_protocol:null)',Source=Apache.Arrow.Adbc.Drivers.Apache,''Type=Thrift.TApplicationException,Message=Required field 'client_protocol' was not present! Struct: TOpenSessionReq(client_protocol:null),Source=Apache.Arrow.Adbc.Drivers.Apache,'",The important part of that error message is An unexpected error occurred while opening the session. 'Required field 'client_protocol' was not present!.
As any developer then does, I started googling that error but didn’t find any pages with that same error for Azure Synapse related Hive issues. But I did find several similar errors with different uses of Hive that were caused by version issues between the client and the server, essentially the client got upgraded beyond what the server version was, which caused a similar error for others.
For my pipeline, I do not control the Hive data source that we were failing to pull from because that is managed by one of my company’s customers. I tried to get information about their Hive version to see if it was something they could fix, but I quickly hit a dead end and they told me to make a support ticket with Microsoft. Which I did.
Thankfully Microsoft was immediately helpful and I got to work with a very kind and knowledgeable support woman, who immediately tracked down and found that the issue I was having was one that the engineering team was already working on resolving. Great! There was a fix already in the works! And a couple days after being told I just needed to wait for the fix to be sent out, I received a message from the support agent asking if I would test out their proposed fix to the problem, which was an updated version of the Self-Hosted Integration Runtime (SHIR) that allowed us to connect our systems to our customer’s.
How to Resolve the Problem
The Self-Hosted Integration Runtime (SHIR) that Microsoft wanted me to test was easy to install on our server where we normally run our SHIR for the workspace I was upgrading. They provided a download link to me, so I hit that then easily install the SHIR like you normally would and it upgraded in place. The version of the SHIR I tested for them was “IntegrationRuntime_5.58.9364.4”.
Once I installed that on our server, I updated the Hive connector again (since I was forced to downgrade while the solution was being developed so I could continue getting our data) and this time, the test connection worked. I then committed the change and ran my pipeline, and it successfully completed the “Copy Data” activity that had been previously failing with the 2.0 version of the connector.
The only problem we have now is that the 2.0 version of the connector seems to have changed how data types are handled for Parquet files in Data Lakes, so now I need to remap data types between our Data Lake and the final data warehouse to get the pipeline completely working again. I had to remove the test SHIR from our production system at that point anyway since they told me we couldn’t use it in production yet, so when I do the official upgrade to the 2.0 Hive connector, I will also need to make that data mapping fix.
As of writing this post, the SHIR that I believe contains the fix is live on the site where you normally download that software, except the version is slightly higher. What’s available on their download site is “IntegrationRuntime_5.58.9377.1”. If you are having the same issue I am with this connector upgrade, give this latest SHIR a try to see if that resolves your issue like the test version did for mine. I will update this post once I have done my final upgrade and have confirmed that the SHIR version available online fixes my problem for good.
Summary
If you started to experience connection failures on your Hive linked service in Synapse after changing the version of the linked service from V1.0 to V2.0, update your Integration Runtime to version 5.58 or later to get the problem fixed. When updating the linked service, there is no mention of needing to upgrade the SHIR unless it is really out of date (when I first tried upgrading the connector I couldn’t because we were on SHIR 5.52), so you will need to be aware of this mismatch yourself.
Let me know down in the comments if you also ran into this issue with the upgrade!
