DnsMonitor This monitor tests the availability of the DNS service on remote IP interfaces. A DNS query is sent to check for a response of either an A or AAAA resource record. The monitor is marked as up if it receives a valid response from the DNS Server. For hostnames that have multiple resource records, it is possible to test if the number of responses are within a given boundary. The monitor can be simulated with the command line tool host: ~ % host -v -t a www.google.com 8.8.8.8 Trying "www.google.com" Using domain server: Name: 8.8.8.8 Address: 8.8.8.8#53 Aliases: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 9324 ;; flags: qr rd ra; QUERY: 1, ANSWER: 5, AUTHORITY: 0, ADDITIONAL: 0 ;; QUESTION SECTION: ;www.google.com. IN A ;; ANSWER SECTION: www.google.com. 283 IN A 74.125.232.17 www.google.com. 283 IN A 74.125.232.20 www.google.com. 283 IN A 74.125.232.19 www.google.com. 283 IN A 74.125.232.16 www.google.com. 283 IN A 74.125.232.18 Received 112 bytes from 8.8.8.8#53 in 41 ms This monitor is intended for testing the availability of a DNS service. To monitor the DNS resolution of some of your nodes from a client’s perspective, use the DNSResolutionMonitor. Monitor facts Class Name org.opennms.netmgt.poller.monitors.DnsMonitor Remote Enabled true Configuration and use Table 1. Optional monitor-specific parameters for the DnsMonitor Parameter Description Default retry Number of retries before the service is marked as down. 0 timeout Time in milliseconds to wait for the A Record response from the server. 5000 port UDP port for the DNS server 53 lookup DNS A Record for lookup test localhost fatal-response-codes A comma-separated list of numeric DNS response codes considered fatal if present in the server’s response. Default value is 2 and corresponds to Server Failed. See RFC 2929 for a list of codes and their meanings. 2 min-answers Minimum number of records in the DNS server response for the given lookup. n/a max-answers Maximum number of records in the DNS server response for the given lookup. n/a This monitor implements the Common Configuration Parameters. Example This example shows how to monitor whether the IP interface from a given DNS server resolves a DNS request. This service should be bound to a DNS server which should be able to give a valid DNS response for DNS request www.google.com. The service is up if the DNS server gives between one and 10 A record responses. Example configuration monitoring DNS request for a given server for www.google.com <service name="DNS-www.google.com" interval="300000" user-defined="false" status="on"> <parameter key="lookup" value="www.google.com" /> <parameter key="fatal-response-code" value="2" /> <parameter key="min-answers" value="1" /> <parameter key="max-answers" value="10" /> </service> <monitor service="DNS-www.google.com" class-name="org.opennms.netmgt.poller.monitors.DnsMonitor" /> To have response time graphs for the name resolution you have to configure RRD graphs for the given ds-names (dns-res-v4, dns-res-v6, dns-res-both, dns-res-either, dns-res-cname-mx) in ${OPENNMS_HOME}/etc/response-graph.properties. DiskUsageMonitor DNSResolutionMonitor