Bug ID 439773: The TMM process may restart and produce a core file when a connection flow is in an invalid TCP state

Last Modified: Sep 13, 2023

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

Known Affected Versions:
10.0.0, 10.2.1, 10.2.3, 10.2.4, 11.2.0, 11.2.1, 11.3.0, 11.4.0, 11.4.1, 11.5.0, 11.5.1

Fixed In:
11.6.0, 11.5.2, 11.4.1 HF9, 11.2.1 HF15, 10.2.4 HF12

Opened: Dec 05, 2013

Severity: 3-Major

Related Article: K17020


TMM will core with panic string "Request for segment from middle of queue."


Traffic disrupted while tmm restarts.


The conditions are infrequent and not all of them are known fully. TCP is in an invalid state for that particular flow, and this flow cannot continue anymore.


This issue has no workaround at this time.

Fix Information

The ASSERTing condition has been converted to RESET that particular flow with the RST cause "Request for segment from middle of queue." This has been decided to be better for product stability as one affected flow does not core the full tmm.

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips