Trapmon Plugin - Showing IP Address Instead of Hostname in Source Column

Geneos Copied

Using the Trapmon plugin in Geneos where SNMP traps show an IP address in the Source column instead of the expected hostname.

Root Cause 1: The sending device cannot consistently resolve its own hostname and falls back to sending its IP address.
Root Cause 2: DNS reverse lookup is not properly configured or is intermittently failing.
Root Cause 3: The device is configured to send traps using IP instead of hostname, or has mixed configuration.

Solution Root Cause 1: Verify the sending device’s DNS configuration and ensure it can consistently resolve its own hostname. If hostname resolution fails, the device may fall back to sending its IP address.
Solution Root Cause 2: Check forward and reverse DNS records for the device. Confirm that the Geneos server can resolve the device IP to hostname using nslookup. Fix any DNS inconsistencies or timeouts.
Solution Root Cause 3: Review the SNMP trap configuration on the device and standardize it to send either hostname or IP consistently, depending on your requirement.