Bug ID 748121: admd livelock under CPU starvation

Last Modified: Jul 06, 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, 13.1.0.8, 13.1.1, 13.1.1.1, 13.1.1.2, 13.1.1.3, 14.0.0, 14.0.0.1, 14.0.0.2, 14.0.0.3, 14.0.0.4, 14.1.0, 14.1.0.1, 14.1.0.2, 14.1.0.3, 14.1.0.4, 14.1.0.5

Fixed In:
15.0.0, 14.1.0.6, 14.0.0.5, 13.1.1.4

Opened: Oct 29, 2018
Severity: 2-Critical

Symptoms

Due to the resources starvation the worker thread of admd does not get CPU for more than two minutes. At the same time, the configuration thread does get CPU. The admd heartbeat failure occurs at 120 seconds. The SOD daemon kills admd. The system posts messages similar to the following: -- notice sod[6783]: 01140041:5: Killing /usr/bin/admd pid 6732 -- warning sod[6783]: 01140029:4: HA daemon_heartbeat ADMD.Anomaly0 fails action is restart. -- warning sod[6783]: 01140029:4: HA daemon_heartbeat ADMD.Publisher0 fails action is restart.

Impact

admd restarts. Behavioral DoS does not work.

Conditions

-- High CPU / memory utilization, -- Very large configuration. Note: There are no known special configuration requirements to have this occur.

Workaround

Reboot the BIG-IP system.

Fix Information

admd livelock event no longer occurs in response to CPU starvation in very large configurations.

Behavior Change