Server/Client Version Compatibility List

In my case I’m working in .NET. We’re running an old 4.0.4 server and I’d like to update the client so I can update the server to follow. I’ve gone straight to EventStore.Client 21.2.2 but I’m getting connection problems even using the examples in the docs. It suggests the two aren’t compatible. It’s doing retries and eventually giving up, using settings that previously worked.

Before I raise a ticket, can I ask if there’s a chart somewhere that will tell me if I’m being silly. Like, perhaps I have to do two or more upgrades to move through the versions?

We don’t currently have a server/client compatibility list, but that would be a useful addition to the docs

The v21.2.2 client supports connecting to v5 servers and up, so it wasn’t tested on v4. That being said, running the client in v5 compatibility mode may work: https://developers.eventstore.com/clients/dotnet/21.2/connecting.html#compatibility-mode

If you still can’t get that working, then you can try the v5.0.11 TCP client, as that should support v4. The v5.0.11 client also has compatibility mode, which can help with an upgrade to v22.10 or above:
https://developers.eventstore.com/clients/dotnet/5.0/connecting.html#compatibility-mode