InteractiveServer SignalR Redis Backplane does not work

[garrettlondon1]

Is there an existing issue for this?

• I have searched the existing issues

Describe the bug

When adding Redis as a SignalR backplane for Blazor Server, it actually does not use Redis to serialize any Circuit or component state

Adding another SignalR hub for real time communications, using a Redis Backplane does work, but this is the same as a standard SignalR app (not Blazor specific)

Expected Behavior

I don't think Redis backplane can handle circuit state at all + constant chatter from websocket changing state so often.

Steps To Reproduce

services.AddRazorComponents()
            .AddInteractiveServerComponents()

services.AddSignalR()
                .AddStackExchangeRedis(o =>
                {
                    o.ConnectionFactory = async writer =>
                    {
                        var connection = await ConnectionMultiplexer.ConnectAsync(configurationOptions);
                        return connection;
                    };
                });

Exceptions (if any)

All InteractiveServer components fail to work if Redis connection is bad - even though it does not effect the main ComponentHub

.NET Version

8.0.401

Anything else?

No response

[garrettlondon1]

It seems like the SignalR connection powering InteractiveServer has absolutely no idea about the Redis backplane, and the Redis Backplane is only applicable to additional hubs added for realtime functionality

https://learn.microsoft.com/en-us/aspnet/core/signalr/redis-backplane?view=aspnetcore-8.0

• If this is the case, the documentation should be updated to say that scaling out SignalR does not work for Blazor Server at all. using a Redis Backplane