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Ensure that your appliances are licensed for discovery.
Add the needed seed routers to each Probe appliance, as described in Defining Seed Routers for Probe Members.
Add the necessary SNMPv1/v2 and SNMPv3 credentials at the Grid level and/or Member/Probe level. For information, see Configuring SNMP1/v2 Credentials for Polling, Configuring SNMPv3 Properties, Defining Seed Routers for Probe Members, and Defining Seed Routers for Probe Members.
If necessary, add CLI Credentials, including device admin username/password tuples and Enable passwords, at the Grid level and/or Member/Probe level, as described in Configuring CLI Discovery Properties and Testing SNMP and CLI Credentials.
If necessary, enable the use of DHCP routers and servers as seeds to increase device discovery, as described in Configuring SNMP1/v2 Credentials for Polling.
If you have extensive end host Ethernet segments connected to Ethernet switches, enable switch port discovery, as described in Defining Seed Routers for Probe Members.
With these settings, the Probe appliances automatically begin discovering network infrastructure devices.
You can elect to immediately discover or schedule discovery of new objects that you create and enable under IPAM or DHCP. Objects that allow immediate discovery include the following:
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You can manually perform discovery on any object at any time by selecting the object and choosing 
Discover Now from the Toolbar. For more information, see Object. When you do so, you see a status icon appear in the Discover Now data column
for the object under IPAM, in the Data Management –> DHCP page and other locations.
By default, Grid discovery settings are the prevailing settings for all newly created objects. You can override basic discovery polling options for networks and DHCP ranges allowing immediate discovery.
In such cases, local settings take priority. Credentials cannot be overridden for networks and DHCP ranges,
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