Bug ID 849861: TMM may crash with FastL4 and HTTP profile using fallback host and iRule command

Last Modified: Nov 22, 2021

Bug Tracker

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

Known Affected Versions:
13.1.0,,,,,,,,, 13.1.1,,

Fixed In:

Opened: Nov 14, 2019
Severity: 3-Major


TMM may crash when FastL4 is used with an HTTP profile and an iRule command. Even if TMM does not crash, the incorrect iRule may prevent the connection from working.


TMM typically crashes; however, whether or not TMM crashes, the invalid use of the pool command results in connection failure.


-- A virtual server configured to use FastL4 with an HTTP profile with a fallback host. -- The virtual server has an iRule that performs a pool pick after the connection is established. Note: Using the pool command after the server-side connection is established is not a valid operation.


Remove the invalid iRule configuration.

Fix Information

This issue no longer occurs.

Behavior Change