Bug ID 493993: TMM crashes on the standby when starting up in HA config and Active processing traffic in APM module

Last Modified: Sep 13, 2023

Affected Product(s):
BIG-IP APM(all modules)

Known Affected Versions:
11.5.1 HF1, 11.5.1 HF2, 11.5.1 HF3, 11.5.1 HF4, 11.5.1 HF5, 11.5.1 HF6, 11.6.2 HF1, 11.2.1, 11.3.0, 11.4.1, 11.6.0, 11.6.1, 11.6.2, 11.6.3,,,,, 11.6.4, 11.6.5,,,

Fixed In:
11.6.0 HF6, 11.5.2, 11.5.1 HF7, 11.4.1 HF7

Opened: Dec 02, 2014

Severity: 2-Critical

Related Article: K15914


On a standby unit, TMM dumps core files when it is starting up and continues to do so when the active unit is handling traffic in the APM module.


TMM on the standby device crashes with SEGV, which causes existing sessions not stored on the standby device and users have to re-login should failover occur.


The issue happens on APM systems when high availability is configured and the following conditions are met: 1. The active device is busy processing traffic. 2. Some sessions on the active device are terminated. 3. The TMM in standby device is starting up.



Fix Information

In APM HA environments, the system now prevents global status from being updated before the initialization is completed on a standby device. TMM on the standby no longer dumps core files on startup.

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips