redisc | A Go redis cluster client built on top of redigo | Command Line Interface library

When you performed make of the redis, you should run as: make BUILD_TLS=yes

I found out that the problem is on redis side. Nodes knew other nodes on right ip address but knew themselves on 127.0.0.1. You may see that here (I masked the real ip address with redis server ip label):

So I just connected to each node and make it meet itself on the right ip asdress (not 127.0.0.1). As you may see, after that it found itself on the right ip address and my problem solved.

Such errors can occur when the said data source is autoconfigured. You can disable Redis autoconfiguration if you're not using it in the application. If you need Redis for the application then you should set spring.redis.host and spring.redis.port.

When you have multiple server instances behind a single load-balancer you need to have sticky sessions enabled, meaning a unique client will only ever connect to a single machine.

You can see some info about the Redis backplane in https://docs.microsoft.com/en-us/aspnet/core/signalr/scale?view=aspnetcore-2.2#redis-backplane

SignalR is a protocol and part of that protocol means that a connection ID will be created on the server during "negotiate". This means you can't just randomly curl the endpoint with an ID because curl doesn't understand the SignalR protocol.

You can read more about the protocol if you're interested at https://github.com/aspnet/AspNetCore/tree/master/src/SignalR/docs/specs

I don't know, but fortunately there's a solution given here:

In Scala all members of a singleton objects should be defined. While you are allowed to modify var members from the outside, take a step back and ask yourself what is the point of having a singleton object in your case if each client can modify its members? You will only end up with spaghetti code.

I would highly recommend using a dependency injection framework (Spring for example) where you can create beans in a specific place then inject them where you need them.

In a nutshell singleton objects should be used when you want to define methods and values (never seen a case where a var is used) that are not specific to each instance of a class (think Java static). In your case, you seem to want different instances (otherwise why should they be set from client code) but want a certain instance to be shared across different clients and this is exactly what dependency injection allows you to do.

If you don't want to use a DI framework and are okay with having clients modify your instances as they please, then simply use a class as opposed to an object. When you use the class keyword, different instances can be instantiated.