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NNM Troubleshooting

NNM server does not appear to be operational

  1. Verify in the SecurityCenter GUI that the NNM server appears as Unable to Connect under Status.
  2. SSH to the remote NNM host to make sure the underlying operating system is operational.
  3. Confirm that the NNM is running (Linux example below):

    # service pvs status

    PVS is stopped
    PVS Proxy (pid 3142) is running

  4. If the NNM service is not running, start the service:

    # service pvs start
    Starting PVS Proxy                                         [  OK  ]
    Starting PVS                                               [  OK  ]

Cannot add a NNM server

  1. Confirm that the NNM proxy is listening on the same port as is configured in SecurityCenter (port 8835 by default):

    # ss -pan | grep 8835
    tcp        0      0*     LISTEN      406/pvs

  2. Check connectivity by telnetting from the SecurityCenter console into the NNM server on port 8835 (the NNM listening port). If successful, the response will include: Escape character is '^]'.

No vulnerabilities are being received from the NNM server

  1. Ensure that the NNM service is running on the NNM host.
  2. Ensure that the NNM is listed in SecurityCenter under Resources > Passive Scanners and that the status of the NNM is listed as Working. Click Edit to ensure that the IP address or hostname, port, username, password, and selected repositories for the NNM are all correct. Edit any incorrect entries to their correct state and click Submit to attempt to reinitialize the NNM scanning interface.

NNM plugins fail to update

  1. Manually test a plugin update under Plugins with Update Plugins. If successful, Passive Plugins Last Updated will update to the current date and time.
  2. Ensure that the SecurityCenter host is allowed outbound HTTPS connectivity to the NNM Plugin Update Site.
  3. For all other NNM plugin update issues, contact Tenable Support at

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