Monitoring the DNS Servers
eG Enterprise prescribes a specialized DNS server monitoring model (see Figure 1), which executes tests on the DNS server at pre-configured intervals to determine the following:
- Resource usage levels of the DNS host
- The TCP connection load on the host
- The health of the network traffic to and from the host
- The availability of the DNS server, and its responsiveness to user requests
Since the DNS service is based on the UDP protocol, the layer model includes measures of the status of the UDP stack of a host. The Application Processes layer tracks the health of the processes corresponding to the DNS server. On Unix systems, the “named” process supports the DNS service.
Since the bottom 4 layers of Figure 1 have been extensively discussed in the Monitoring Unix and Windows Servers, let us focus only on the DNS Service layer.