yes jonathan, i also have 10.3.11.75:8080 as virtual server also. if i don't enable 10.4.0.10:8080, the 10.3.11.75:8080 can work properly. but if i enable 10.4.0.10:8080 and flow the traffic from the router, it can work for few seconds than hangs. 10.3.11.75:8080 can work again if i restore the config. Or I don't have to restore the config, but stop the flow.
My colleague (from other company) takes control of the router. I cannot do NAT there, because the bigip will be handling A LOT of traffic. If I do NAT on the router, I'm afraid it will hang also even in normal traffic condition. That's why the client are letting the bigip handling the NAT.
Nimbostratus