Bug ID 553735: TMM core on HTTP response with steering action.

Last Modified: May 14, 2019

Bug Tracker

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

Known Affected Versions:
11.6.0, 11.6.0 HF1, 11.6.0 HF2, 11.6.0 HF3, 11.6.0 HF4, 11.6.0 HF5, 11.6.0 HF6, 11.6.0 HF7, 11.6.0 HF8, 11.6.1, 11.6.1 HF1, 12.0.0, 12.0.0 HF1, 12.0.0 HF2

Fixed In:
12.1.0, 12.0.0 HF3, 11.6.1 HF2

Opened: Oct 21, 2015
Severity: 2-Critical
Related AskF5 Article:


TMM core on HTTP response with steering action.


TMM cores trying to steer the existing connection. Traffic disrupted while tmm restarts.


HTTP profile is not attached to a PEM virtual server receiving the HTTP response. In this case, on receiving a connection request from the client, the BIG-IP system establishes server-side connection without waiting for the HTTP request from the client. Meanwhile, a steering policy got installed. The server responds with an HTTP request timeout message.


To avoid this issue, attach an HTTP profile to the PEM virtual server.

Fix Information

TMM no longer cores on HTTP response with steering action.

Behavior Change