Network Management

Advanced alerts for Thin Access Points

This article describes how the advanced alerts for thin APs work, how to enable them, and other hints. [Advanced] Thin AP Disappeared from WLC and [Advanced] Thin AP Down alerts respect the primary/secondary WLC settings for your APs.

First published date

6/4/2024 5:01 AM

Last published date

6/4/2025 3:33 PM

Overview

Learn about advanced alerts that respect the primary/secondary Access point configuration on your wireless controllers:
  • [Advanced] Thin AP Disappeared from WLC
  • [Advanced] Thin AP Down

Product section

Network Performance Monitor

Resolution

Advanced alerts

If you define primary/secondary wireless controllers (WLCs) for specific access points (APs), use the following advanced alerts:

  • [Advanced] Thin AP Disappeared from WLC: This alert triggers when an AP disappears from a WLC in the primary-secondary WLC pair and does not appear on the other WLC from the WLC pair for two poll cycles.
  • [Advanced] Thin AP Down: This alert triggers when an AP goes down on a WLC in the primary-secondary WLC pair and does not appear as up on the other WLC from the pair within two poll cycles.

Configure advanced thin AP alerts

  • Check the advanced configuration for wireless monitoring.
    1. Go to advanced settings on your SolarWinds Platform polling engine. See Access the Advanced Configuration settings in the SolarWinds Platform Web Console.
    2. Search for Wireless. in the settings.
    3. Clear the Wireless.RemoveDisappearedAPs setting. This setting clears APs from the database if a WLC doesn't provide information about the AP in two polls. WLC nodes might not be polled at the same time, thus clearing this setting keeps the APs in the database long enough for the SolarWinds Platform to check whether the AP appears for the second WLC in the pair.
    4. Clear the Wireless.TriggerThinApDisappearedEventByCollectorService setting. This setting triggers a Thin AP disappeared event when the AP disappears. Advanced configuration needs to check the AP for both WLCs. Clearing this setting prevents triggering false-positive events.
  • Ensure that primary and secondary WLCs have the same poll interval. If possible, monitor them with the same polling engine.
  • Disable all other active wireless alerts for detecting down/disappeared APs to avoid false positive alerts.

Clear disappeared AP alerts

To clear triggered alerts for disappeared APs, go to advanced settings, enable the Wireless.RemoveDisappearedAPs setting, and disable the settings again after 15-20 minutes.
This clears false-positive alerts for disappeared/down alerts. 

Replace old WLCs with a new WLC primary-secondary pair, move APs to new hardware without triggering false-positive alerts

  1. Before you start decommissioning WLCs, unmanage the original WLCs.
  2. Replace the hardware.
  3. Add the new WLCs for monitoring.
  4. Poll the new WLCs and wait for wireless data to appear in the web console.
  5. Delete the old WLC.
  6. Repeat the steps for all other WLCs.