Troubleshooting guide

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Cisco Wide Area Application Services Configuration Guide
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Chapter 1 Configuring Other System Settings
Configuring Alarm Overload Detection
the status of the nonresponsive devices as offline. Because UDP heartbeats require less processing than
a getUpdate request, they can be transmitted more frequently, and the WAAS Central Manager can detect
offline devices much faster.
You can enable or disable this feature, specify the interval between two UDP packets, and configure the
failed heartbeat count. Heartbeat packet rate is defined as the interval between two UDP packets. Using
the specified heartbeat packet rate and failed heartbeat count values, the WAAS Central Manager GUI
displays the resulting offline detection time as a product of heartbeat rate and failed heartbeat count. If
the fast detection of offline devices is enabled, the WAAS Central Manager detects devices that are in
network segments that do not support UDP and uses getUpdate (get configuration poll) request to detect
offline devices.
By default, the feature to detect offline devices more quickly is not enabled.
Configuring Alarm Overload Detection
WAAS devices can track the rate of incoming alarms from the Node Health Manager. If the rate of
incoming alarms exceeds the high-water mark (HWM), then the WAAS device enters an alarm overload
state. This situation occurs when multiple applications raise alarms at the same time to report error
conditions. When a WAAS device is in an alarm overload state, the following occurs:
• SNMP traps for subsequent alarm raise and clear operations are suspended. The trap for the raise
alarm-overload alarm and the clear alarm-overload alarm are sent; however, traps related to alarm
operations between the raise alarm-overload alarm and the clear alarm-overload alarm operations
are suspended.
• Alarm overload raise and clear notifications are not blocked. The alarm overload state is
communicated to SNMP and the Configuration Management System (CMS). However, in the alarm
overload state, SNMP and the CMS are not notified of individual alarms. The information is only
available by using the CLI.
• The WAAS device remains in an alarm overload state until the rate of incoming alarms decreases to
the point that the alarm rate is less than the low-water mark (LWM).
• If the incoming alarm rate falls below the LWM, the WAAS device comes out of the alarm overload
state and begins to report the alarm counts to SNMP and the CMS.
When the WAAS device is in an alarm overload state, the Node Health Manager continues to record the
alarms being raised on the WAAS device and keeps a track of the incoming alarm rate. Alarms that have
been raised on a WAAS device can be listed using the show alarm CLI commands that are described in
the Cisco Wide Area Application Services Command Reference.
To configure alarm overload detection for a WAAS device (or device group), follow these steps:
Step 1 From the WAAS Central Manager menu, choose Devices > device-name (or Device Groups >
device-group-name).
Step 2 Choose Configure > Monitoring > Alarm Overload Detection. The Alarm Overload Detection
Settings window appears.
Step 3 Uncheck the Enable Alarm Overload Detection check box if you do not want to configure the WAAS
device (or device group) to suspend alarm raise and clear operations when multiple applications report
error conditions. This check box is checked by default.
Step 4 In the Alarm Overload Low Water Mark (Clear) field, enter the number of incoming alarms per second
below which the WAAS device comes out of the alarm overload state.