Monitoring with Cisco WAAS › How Cisco WAAS Works as a Monitoring Device › How Monitoring Works when Optimization Stops › Temporary Interruptions

Temporary Interruptions

If the management console temporarily stops receiving segmented application performance data from a Cisco WAE, the management console uses data from the unoptimized server SPAN to report on the application in the Server segment. The management console uses several criteria to determine whether an interruption is temporary or permanent, but a temporary interruption is typically less than 20 minutes.

While the management console temporarily reports the unoptimized application data from the server’s mirrored switch port in the Server segment:

• All metrics on the Optimization page are accurate, although not all metrics will populate.
• Measurements for the unoptimized sessions do not affect the Client or WAN segments.
• The Server segment is accurate because the management console always uses the more accurate data from the server’s mirrored switch port.
• Network Round Trip Time [Server], which is displayed on the Engineering page, shows an increase because it no longer gets 100% local ACKs. The spillover measurements show actual Network Round Trip Time out to the client.
• RetransDelay [Server] and PacketLossPct [Server] might also show increases.

When optimization data resumes, the management console automatically reports the segmented application data in the application’s Client, WAN, and Server segments.

Temporary interruptions to optimized monitoring can occur, for example, when:

• Optimization stops. This can occur when a Cisco WAE does not have the resources to optimize additional sessions. The unoptimized sessions are called spillover.
• Monitoring stops. This can occur when a CA Standard Monitor or CA Multi-Port Monitor stops receiving packet digests from its assigned Cisco WAE devices, for example, when there is a disruption in the link between a Cisco WAE and its assigned monitoring device, or when the Cisco WAE is not configured to export response time data.