Device Autodiscovery : Requirements for device discovery
  
Requirements for device discovery
The following is required for SNMP discovery:
SNMPv1, v2c, or v3 must be enabled on all network devices that you want to discover (read-only level is adequate).
NetIM must have access to network devices using SNMP (default SNMP port is 161).
You must provide the set of SNMP read-only community strings or v3 credentials defined for the network domain of interest. See Global credentials lists.
You must provide the IP address of at least one router or switch in each separately connected component that you want to discover.
You must have permission to poll devices on your network using SNMP.
The following is required for autoconfiguration of device entries:
Network access to devices is required on the following ports for CLI access:
telnet (23)
SSH (22)
You must provide the credentials needed for CLI login for devices in the network domain of interest. See Global credentials lists.
Related topics
Device Autodiscovery
SNMP discovery
Device entries created in Device Manager
Configure discovery range
Troubleshooting device discovery