Operation Manual – Cluster ManagementH3C S3610&S5510 Series Ethernet Switches Chapter 1 Cluster Management Configuration1-4z The management device adds or deletes a member device and modifies clustermanagement configuration according to the candidate device informationcollected through NTDP.I. Introduction to NDPNDP is used to discover the information about directly connected neighbors, includingthe device name, software version, and connecting port of the adjacent devices. NDPworks in the following ways:z A device running NDP periodically sends NDP packets to its neighbors. An NDPpacket carries NDP information (including the device name, software version, andconnecting port, etc.) and the holdtime, which indicates how long the receivingdevices will keep the NDP information. At the same time, the device also receivesbut does not forward the NDP packets from its neighbors.z A device running NDP stores and maintains an NDP table. The device creates anentry in the NDP table for each neighbor. If a new neighbor is found, meaning thedevice receives an NDP packet sent by the neighbor for the first time, the deviceadds an entry in the NDP table. When another NDP packet is received, if the NDPinformation carried in the NDP packet is different from the stored information, thecorresponding entry in the NDP table is updated; otherwise, only the holdtime ofthe entry is updated. If no NDP information from the neighbor is received within theholdtime, the corresponding entry is removed from the NDP table.NDP runs on the data link layer, and therefore supports different network layerprotocols.II. Introduction to NTDPNTDP is a protocol used to collect network topology information. NTDP providesinformation required for cluster management: it collects topology information about thedevices within the specified hop count, to identify candidate devices for a cluster.Based on the neighbor information stored in the neighbor table maintained by NDP,NTDP on the management device advertises NTDP topology collection requests tocollect the NDP information of each device in a specific network range as well as theconnection information of all its neighbors. The information collected will be used by themanagement device or the network management software to implement requiredfunctions.When a member device detects a change on its neighbors through its NDP table, itinforms the management device through handshake packets. Then the managementdevice triggers its NTDP to perform specific topology collection, so that its NTDP candiscover topology changes timely.The management device collects topology information periodically. You can alsoadministratively launch a topology information collection with commands. The processof topology information collection is as follows:
