Troubleshooting SNMP

About this task

Troubleshoot Simple Network Management Protocol (SNMP) if the network management station (NMS) does not receive traps.

Verify the management configurations for the management station. Also verify the management station setup. If the management station can reach a device but not receive traps, verify the trap configurations (that is, the trap destination address and the traps to be sent).

If you enable enhanced secure mode, the switch does not support the default SNMPv1 and default SNMPv2 community strings, and default SNMPv3 user name. The individual in the administrator access level role can configure a non-default value for the community strings, and the switch can continue to support SNMPv1 and SNMPv2. The individual in the administrator access level role can also configure a non-default value for the SNMPv3 user name and the switch can continue to support SNMPv3. If you disable enhanced secure mode, the SNMPv1 and SNMPv2 support for community strings remains the same, and the default SNMPv3 user name remains the same. Enhanced secure mode is disabled by default.

Procedure

  1. From the NMS, ping the IP address for the switch. If you can ping successfully, the IP address is valid and you may have a problem with the SNMP setup.

    If you cannot ping the switch, you have a problem with either the path or the IP address.

  2. Telnet to the switch.

    If you can Telnet, the switch IP address is correct.

  3. If Telnet does not work, connect to the console port using a serial line connection and ensure that the IP address configuration is correct.
  4. If the management station is on a separate subnet, make sure that the gateway address and subnet mask are correct.
  5. Using a management application, perform an SNMP Get request and an SNMP Set request (that is, try to poll the device or change a configuration using management software).
  6. If you cannot reach the device using SNMP, access the console port, and then ensure that the SNMP community strings and traps are correct.
  7. Use sniffer traces to verify that the switch receives the poll.
  8. Use sniffer traces to verify that the NMS receives the response.
  9. Verify that the data in the response is the data that was requested.