Bug ID 461578: Large objects in the session database can cause TMM to core in HA configurations

Last Modified: Apr 28, 2025

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

Known Affected Versions:
11.0.0, 11.1.0, 11.2.0, 11.2.1, 11.3.0, 11.4.0, 11.4.1, 11.5.0, 11.5.1, 11.5.1 HF1, 11.5.1 HF2, 11.5.1 HF3, 11.5.1 HF4, 11.5.1 HF5

Fixed In:
11.6.0, 11.5.2, 11.5.1 HF6

Opened: May 09, 2014

Severity: 3-Major

Related Article: K15476

Symptoms

Large objects in the session database can cause TMM to core in HA configurations.

Impact

The Traffic Management Microkernel (TMM) may produce a core file when using an iRule table command with large datasets, and the BIG-IP system will temporarily fail to process traffic as it recovers from TMM restarting.

Conditions

This issue occurs when all of the following conditions are met: An iRule contains a table command, such as set, add or replace, which attempts to insert a large set of data (more than 128k): -- Session mirroring is enabled between BIG-IP high-availability devices. Note: Session mirroring is enabled by default through the StateMirror.MirrorSessions database variable.

Workaround

To work around this issue, revise the iRule to avoid insertion of large datasets. Note: Changing the design of an iRule may have additional effects on traffic processing. Ensure any modification is compatible with your environment.

Fix Information

This release provides improved handling of large objects in the session database.

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips