If trap messages are unreadable, which scenario could explain this besides missing device MIBs?

If trap messages are unreadable, which scenario could explain this besides missing device MIBs?

• A. It uses SNMPv3 and has not been added as a monitored node for authentication
• B. Only SNMP v2 traps are configured
• C. The SNMP community string is read-only
• D. The device is not sending traps at all

Answer: (A)

Unreadable trap messages usually come from a mismatch in SNMP security settings, not from missing MIBs. If a device uses SNMPv3 and the NPM hasn’t been configured with the corresponding SNMPv3 credentials (the user, authentication, and privacy settings) for that device, the manager cannot authenticate or decrypt the traps. Without proper authentication configuration, the traps arrive but can’t be interpreted, so their contents appear unreadable. This is why that scenario best explains unreadable traps beyond missing MIBs. Traps configured only for SNMPv2 do not inherently become unreadable; they are generally readable if MIBs are present. A read-only community string affects GET operations more than trap readability, and if the device isn’t sending traps at all, you wouldn’t see unreadable traps—just nothing to read.

Unreadable trap messages usually come from a mismatch in SNMP security settings, not from missing MIBs. If a device uses SNMPv3 and the NPM hasn’t been configured with the corresponding SNMPv3 credentials (the user, authentication, and privacy settings) for that device, the manager cannot authenticate or decrypt the traps. Without proper authentication configuration, the traps arrive but can’t be interpreted, so their contents appear unreadable. This is why that scenario best explains unreadable traps beyond missing MIBs.

Traps configured only for SNMPv2 do not inherently become unreadable; they are generally readable if MIBs are present. A read-only community string affects GET operations more than trap readability, and if the device isn’t sending traps at all, you wouldn’t see unreadable traps—just nothing to read.