26-9of the devices in a specified range, thus avoiding unlimited topology collection.After the interval for collecting topology information is configured, the device collects the topologyinformation at this interval.To avoid network congestion caused by large amounts of topology responses received in shortperiods:z Upon receiving an NTDP topology collection request, a device does not forward it, instead, it waitsfor a period of time and then forwards the NTDP topology collection request on its firstNTDP-enabled port.z On the same device, except the first port, each NTDP-enabled port waits for a period of time andthen forwards the NTDP topology collection request after the previous port forwards the NTDPtopology collection request.Follow these steps to configure NTDP parameters:To do… Use the command… RemarksEnter system view system-view —Configure the maximum hopsfor topology collection ntdp hop hop-value Optional3 by default.Configure the interval to collecttopology information ntdp timer interval-time Optional1 minute by default.Configure the delay to forwardtopology-collection requestpackets on the first portntdp timer hop-delay time Optional200 ms by default.Configure the port delay toforward topology collectionrequest on other portsntdp timer port-delay time Optional20 ms by default.The two delay values should be configured on the topology collecting device. A topology collectionrequest sent by the topology collecting device carries the two delay values, and a device that receivesthe request forwards the request according to the delays.Manually Collecting Topology InformationThe management device collects topology information periodically after a cluster is created. In addition,you can configure to manually initiate topology information collection, thus managing and monitoringthe device on real time, regardless of whether a cluster is created.Follow these steps to configure to manually collect topology information:To do… Use the command… RemarksManually collect topology information ntdp explore Required
