Name Resolutions Test

This test emulates a client accessing a DNS server to issue a query. The query can either request the DNS server to resolve a domain name to an IP address or vice versa. Based on the response reported by the server, measurements are made of the availability and responsiveness of the DNS server.

The DNS service is organized hierarchically, i.e., one DNS server can forward a client request to another server to resolve the client’s query. To ensure that the results of the query reflect the state of a DNS server in isolation, a non-recursive query is issued by this test.

Target of the test : A DNS server

Agent deploying the test : An external agent

Outputs of the test : One set of results per target configured.

Configurable parameters for the test

Parameter	Description
Test Period	How often should the test be executed.
Host	The IP address of the host for which this test is to be configured.
Port	The port on which the specified host is listening
Targets	The IP address or host name to be resolved during the test. Multiple targets can be specified as a comma-separated list.
Recursive	A DNS server supports two types of queries. For a non-recursive query, the DNS server attempts to respond to the request based on its local cache only. For a recursive query, a DNS server may use other DNS servers to respond to a request. The Recursive flag can be used to determine the type of queries to be issued to a DNS server.
UseEXE	In older versions of the eG Enterprise Suite, this test used native APIs to collect the desired metrics. To ensure backward compatibility with older versions of the solution, this flag has been set to Yes by default. Set this flag to No if you want the test to use Java APIs instead to determine the availability and responsiveness of the DNS server. This flag is only relevant if the test is being executed by an external agent operating on a Windows host.

Measurements made by the test

Measurement	Description	Measurement Unit	Interpretation
DNS availability	Whether a successful response is received from the DNS server in response to the emulated user request.	Percent	An availability problem can be caused by different factors - e.g., the server process may not be up, a network problem may exist, or there could be a configuration problem with the DNS server.
DNS response time	Time taken (in seconds) by the server to respond to a request.	Secs	An increase in response time can be caused by several factors such as a server bottleneck, a configuration problem with the DNS server, a network problem, etc.