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Is there a way to test if a specific device on our network has SNMP enabled (is listening for SNMP-specific traffic) without knowing the community string and without having access to its settings?

(A device that is supposed to have SNMP enabled does not respond to any SNMP requests from our Solarwinds server, and I wanted to see if this is a device problem, or a network path (firewall?) problem. The device can be pinged and trace-route'd successfully.)

Thank you for any ideas.

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Possible answer: check if the device is listening on ports 161 (to a lesser extent, on 162), i.e. do a port scan on these specific ports usually reserved for SNMP uses.

Does this sound like a good answer?

(Did a test and it seems to work: Network Utility on a Mac, "port scan" on a target IP, on port 161. If the scan has a timeout, SNMP is likely not configured - or firewalled for the source IP. If the scan completes successfully and quickly, the device is listening on 161, which means that it likely has an active snmp(d) service.)

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    I was thinking along the same lines. It depends what the scan-for-listeners involves; you may well get some false positives from devices with firewalls-that-reject (rather than those that drop), but it'll certainly give you a short list to probe more fully. – MadHatter Nov 17 '14 at 11:21

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