Hi,
The active and standby ACE process probes independently, so, it can happen that one is seeing the server as operational while the other one is not. It would be normal
However, from what you are describing, it seems your probes are failing quite often. My guess is that you set the "faildetect" parameter to something very low. In that situation, even a short temporary failure could bring the server down on the ACE. You should make sure to set this parameter to a value high enough to ensure that only a real failure of the server brings the server down on the ACE
Regards
Daniel