Hello Fatih,
I guess the your described challanges are not caused by the NTP, but by using a Proxy Server.
There are some known limitations, when a Proxy Server is used. Could you describe your network setup in more detail. Where is your DNS Server located, which is resolving the DNS Names of the IE HUB?
These known limitations are already fixed the the new IEM V2, which can be deployed in an existing Kubernetes Cluster. So if you are familiar with Kubernetes, the new IEM V2 is the perfect fit as it brings also additional benefits and features.
Next to the Kubernetes based IEM V2 there will be further types of the IEM V2 in future releases.