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

layermodel-final

Figure 1 : eG Enterprise's model of a DNS server

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.