The Default IP_Route Connectivity Polling setting determines the polling intervals that are used by the IP Availability Manager to monitor default routes. The IP Availability Manager monitors the default routes by probing the SNMP ipRouteTable (.1.3.6.1.2.1.4.21.0.0.0.0) on certain router devices.
Routers in an organization generally point the default route to the router that has a connection to a network service provider. By doing so, packets with destinations that are outside of the organization’s IP address space will be forwarded to that service provider. The default route address in IPv4 is 0.0.0.0/0.
The lack of a default route on a router is a good indication that an organization’s service provider is having connectivity issues.
When default-route polling fails, the IP Availability Manager generates a MissingDefaultRoute event. Specifically, the IPRoute object that is created as part of the Default IP_Route Connectivity Polling setting, itself, generates the MissingDefaultRoute event.
The IP Manager Reference Guide provides information on the Default IP_Route Connectivity Polling setting parameters.