Tcp synchronisation with LVM + HA Proxy + web server (cluster 2 node each)

Hello everyone,
I’m new to clustering, I have a configuration that works, but I have a problem and I don’t know if I’m doing things right or not.

I’ll explain my config to you:
I have a cluster of 2 ha-proxy in reverse proxy, which point to a web server, also in a 2 node cluster.

Ultimately, there will be much more than 2 web servers (several backends)

I set up these confs with keepalived + haproxy (and sticky-sessions) and it works very well.

Where I have a problem is with the download. if a file is downloaded from the web server, and a node goes down, the download stops. it is not taken over by the other ha-proxy.

Should we use LVS (or ipvs) to synchronize the TCP states of the 2 ha-proxies so that there is continuity of service?

I tried, but since I can’t come up with anything convincing, I think I’m going the wrong way.

Thank you for your help, I will post my config if necessary, but explanations might be enough for me.

and sorry for my spelling, I’m not English.
Good day to everyone.

Haproxy cannot take over a TCP connection from another instance.

Only if you remove haproxy and stick to Layer4 IPVS you can do this, afaik.