The DnsMonitor enables OpenNMS to monitor the ability of a DNS server to resolve names, and to report on the latency of this service.

Configuration

The default version of poller-configuration.xml shipped with OpenNMS has the DnsMonitor configured and enabled. Usually no configuration is necessary.

Service Parameters

Like all monitors, the service tag can take a number of parameters:

name

the name of the service in OpenNMS, this must be the same as the service name specified in capsd-configuration.xml.

interval

how often (in milliseconds) to perform a poll using this monitor

user-defined

whether or not this service is user-defined, used primarily in the UI

status

whether or not the monitor is enabled

Monitor-Specific Parameters

DnsMonitor also takes the following monitor-specific parameters:

port

The UDP port on which the monitor should contact the DNS servers that it is monitoring

lookup

The DNS name that the service monitor should attempt to resolve. Defaults to localhost. All DNS servers should answer for this name, but some do not. Specify a name here for which you know your DNS servers will answer.

fatal-response-codes

Available starting from OpenNMS 1.6.10. A comma-separated list of numeric DNS response codes that will be considered fatal if present in the server's response. Default value is 2, which corresponds to Server Failed. A list of codes and their meanings is found in RFC 2929.

• This feature was enhanced or modified in version 1.6.10
• This feature was enhanced or modified in version 1.7.10