Scalability

Network Discovery is designed to find thousands of devices and clients. Tests of Network Discovery have discovered networks that contain approximately 60,000 resources. If you plan to run discoveries of this scale, you should consider the following issues:

• During a large discovery, large numbers of DDRs are produced. For this reason, you should schedule Network Discovery so that Discovery Data Manager has as long as possible to process the DDRs.
• Discovery Data Manager processes DDRs at an approximate rate of two to five DDRs per second.
• The default duration of Network Discovery is two hours. If you are trying to discover large numbers of network devices and clients, two hours might not be enough time for discovery to complete. To ensure enough time for Network Discovery on large networks, simply increase the duration, run the discovery a few subnets at a time, and run it overnight or on the weekend.

If for some reason the discovery terminates early, Discovery Data Manager will create DDRs for each discovered device whose IP address and subnet mask have been found and whose IP address is within the subnets defined in the Subnets tab of the Network Discovery Properties dialog box. Network Discovery uses information from DHCP servers and SNMP to communicate directly with devices such as routers and then uses the routers’ ipNetToMedia tables and Router Interface tables to obtain subnet masks. If Network Discovery cannot find a subnet mask, it will not create a DDR for that resource.