DNS Application Processing Times
The DNS Application Processing Time exceeds the critical value set in Expert Thresholds. "Application Processing Time" measures the time spent waiting for the application or server, as opposed to network latency. Network Latency plus application processing time is referred to as Session Delay, which is tracked by a separate Expert Threshold.
Possible reasons for the event:
There is a hardware or software problem at the application end. Perhaps the DNS server hardware is overloaded with disk I/0 requests, or some other system component (for example, the CPU or NIC) is too slow given the traffic it is expected to handle.
The DNS Server or client is misconfigured in some way.