HTTP Connections and Timeouts

I have a simple HTML profile attached to a VIP along with a simple TCP (no modifications) profile. We're having some issues where our web servers talk to the VIP to talk to our app servers.

 

Web servers -----> F5 VIP -----> App Servers

 

The web servers are seeing the connection closed but on the app servers we aren't seeing these logs. So far it looks like the client side connection is being closed while the server side connection remains open or possibly the server side is closing and the client side isn't being notified. I'm not really sure to be honest. I know the HTTP version used is HTTP1.1 so I understand that the client believe this should be a persistent connection until the Connection: Close is received in the header. Does the F5 send this to the client in the event the server side connections are closed?

 

I've looked into the Oneconnect profile and that seems to be a reasonable way forward based on a lot of what I see on the forums but I wanted to get some input here. The TCP idle time is currently set to 300 seconds and the windows default TCP idle time is 120 seconds so we shouldn't be running into a TCP keepalive issue. The reason why is because this was all working fine before we put the F5s into production. This issue with closing connections is new to the F5 implementation. Thoughts