Could Push feature work in HA environment.

I am using Vaadin 8.9.0 currently.
Because customer request, we have to support HA environment, what I am doing is to do the session replication. otherwise I have no idea how to support HA environment without user login again when one server node crashes.

everything seems ok till I got the Push issue. in the HA environment, It seems everything goes well. while the method is called and UI.getCurrent().access() runs. but the page just has no response.
it seems the communication between the client and the server is broken.
I am using redis to store the session data, and all the UI has been serialized and saved to redis when one request finish. and when another request comes, it will fetch the data from redis and deserailize it.

Does anybody has any idea about this?

This is a challenging combination, and I guess what you are trying to do is not supported out of the box, see discussion here