Bug ID 458564: TMM crash using cloned pool with packet marked for TSO

Last Modified: Oct 06, 2020

Bug Tracker

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

Known Affected Versions:
11.4.0, 11.4.1

Fixed In:
11.4.1 HF6

Opened: Apr 23, 2014
Severity: 3-Major
Related AskF5 Article:


TMM can crash if the cloned pool doesn't support TCP segmentation offload (TSO), but receives a packet that is marked for TSO.


Traffic disrupted while tmm restarts.


If a virtual is configured with a clone pool, the original flow supports TSO and the cloned pool doesn't not support TSO, then a packet received on the original flow and is marked for TSO can cause a TMM crash when sent to the clone pool member.


To workaround this issue disable TSO. This can be done by modifying the DB variable tm.tcpsegmentationoffload: tmsh modify sys db tm.tcpsegmentationoffload value disable

Fix Information


Behavior Change