Bug ID 718685: The measured number of pending requests is two times higher than actual one

Last Modified: May 14, 2019

Bug Tracker

Affected Product:  See more info
BIG-IP ASM(all modules)

Known Affected Versions:
13.1.0, 13.1.0.1, 13.1.0.2, 13.1.0.3, 13.1.0.4, 13.1.0.5, 13.1.0.6, 13.1.0.7

Fixed In:
14.1.0, 13.1.0.8

Opened: May 06, 2018
Severity: 3-Major

Symptoms

The measured number of pending requests is two times higher than actual.

Impact

Server stress mechanism is more sensitive than planned. A temporary traffic spike can cause unnecessary DoS mitigation start. Note: The admd process provides stress-based DoS detection and mitigation control. When admd is not running, there is no stress-based anomaly detection or behavioral statistics aggregation.

Conditions

Virtual server configured with a Behavioral DoS profile.

Workaround

Modify the adm.health.sensitivity value. For example, to change health sensitivity from 50 to 500, run the following command: tmsh modify sys db adm.health.sensitivity value 500

Fix Information

Fixed initial adm flow sampling, so that the measured number of pending requests now equals actual.

Behavior Change