A network node is being added; however, the SNMP validation test is failing.

The best answer from the available options is A, but the wording is poor. SolarWinds’ troubleshooting guidance says that when SNMP data does not return as expected, administrators should confirm that the node responds with a proper OID by using the MIB Browser or another SNMP request tool, and can also use the SolarWinds SNMP Walk tool to troubleshoot connection/OID issues. Since the question already confirms credentials and firewall ports, repeating the community string check is redundant. Polling with an agent does not fix SNMP validation from the server, and the MIB database service is not the first logical validation step. A is closest because it tests whether the device actually returns OID data.

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