The client noticed that the server is not a supported distribution of Elasticsearch (NEST 7.16 to Elasticsearch 7.9.0)

NEST/Elasticsearch.Net version: 7.16.0

Elasticsearch version: 7.9.0

.NET runtime version: 4.7.2

Operating system version: Windows 10 / Server 2019

Description of the problem including expected versus actual behavior: I was previously using NEST/Elasticsearch.NET 7.9.0, but we are looking to upgrade to 7.16.2 for the LOG4J vurnability. Looking at your official documentation I noticed the following:

I have a 7.0 server, what client should I use?

Always use the latest minor version of the client within that major version, so in this instance, at time of writing, this is version 7.14.0. The reason being is that 7.14.x will contain many bug fixes not present in the 7.0.0 version of the client.

Client methods which call endpoints added to Elasticsearch since 7.0.0 will fail due to those endpoints not existing on the server.

So I upgraded my NEST/ElasticSearch to the latest minor version (7.16). Now when I try to connect to our Elastic Cluster I get the exception “The client noticed that the server is not a supported distribution of Elasticsearch”.

I would expect this to just work, according to your official documentation?

Steps to reproduce:

1. Have ElasticSearch 7.9.0
2. Have NEST/ElasticSearch 7.16.0
3. Try to connect to ElasticSearch 7.9.0

Expected behavior I expected to be able to connect to the ElasticSearch cluster.

Provide ConnectionSettings (if relevant):

Provide DebugInformation (if relevant):

[stevejgordon]

@Schoof-T You’re most welcome! I’ll close this issue for now since the client is behaving correctly. We can re-open if anything fails after the upgrade.

[Schoof-T]

Thanks for providing that information @Schoof-T. Unfortunately, this may be a bug in the MSI installer causing the build_flavor to be unknown and therefore causing the product check to fail. The MSI is considered beta and will no longer be produced after 7.16.2. In your case, I think you’ll need to first upgrade the nodes to the latest release of Elasticsearch using the zip package. Hopefully, that will resolve the unknown build_flavor that is reported. The 7.9.0 client should continue to be compatible with this newer server version. Once the server is upgraded and reporting a known build_flavor you can then update to the latest client. Note that I haven’t tested this myself and I’d advise testing your scenario in a non-production environment first to ensure that it works as expected.

I will test again after upgrading to 7.16.2 using the ZIP file. Thanks for the advice.