Troubleshooting guide

1-22
Cisco Wide Area Application Services Configuration Guide
OL-26579-01
Chapter 1 Configuring Other System Settings
Configuring Faster Detection of Offline WAAS Devices
To configure fast detection of offline WAAS devices, follow these steps:
Step 1 From the WAAS Central Manager menu, choose Configure > Global > Fast Device Offline Detection.
The Configure Fast Offline Detection window appears.
Note The fast detection of offline devices feature is in effect only when the WAAS Central Manager
receives the first UDP heartbeat packet and a getUpdate request from a device.
Step 2 Check the Enable check box to enable the WAAS Central Manager to detect the offline status of devices
quickly.
Step 3 In the Heartbeat Rate (Seconds) field, specify how often devices should transmit a UDP heartbeat packet
to the WAAS Central Manager. The default is 30 seconds.
Step 4 In the Heartbeat Fail Count field, specify the number of UDP heartbeat packets that can be dropped
during transmission from devices to the WAAS Central Manager before a device is declared offline. The
default is 1.
Step 5 In the Heartbeat UDP Port field, specify the port number using which devices will send UDP heartbeat
packets to the primary WAAS Central Manager. The default is port 2000.
The Maximum Offline Detection Time field displays the product of the failed heartbeat count and
heartbeat rate.
Maximum Offline Detection Time = Failed heartbeat count * Heartbeat rate
If you have not enabled the fast detection of offline devices feature, then the WAAS Central Manager
waits for at least two polling periods to be contacted by the device for a getUpdate request before
declaring the device to be offline. However, if you enable the fast detection of offline devices feature,
then the WAAS Central Manager waits until the value displayed in the Maximum Offline Detection Time
field is exceeded.
If the WAAS Central Manager receives the Cisco Discovery Protocol (CDP) from a device, then the
WAAS Central Manager GUI displays the device as offline after a time period of 2* (heartbeat rate) *
(failed heartbeat count).
Step 6 Click Submit.
Note Any changes to the Configure Fast WAE offline detection page in the Central Manager could result in
devices temporarily appearing to be offline. Once the configuration changes are propagated to the
devices, they show as online again.
About Faster Detection of Offline Devices
Communication between the WAAS device and WAAS Central Manager using User Datagram Protocol
(UDP) allows faster detection of devices that have gone offline. UDP heartbeat packets are sent at a
specified interval from each device to the primary WAAS Central Manager in a WAAS network. The
primary WAAS Central Manager tracks the last time that it received a UDP heartbeat packet from each
device. If the WAAS Central Manager has not received the specified number of UDP packets, it displays