Bug ID 771173: FastL4 profile syn-cookie-enable attribute is not being rolled forward correctly.

Last Modified: Nov 07, 2022

Bug Tracker

Affected Product:  See more info
BIG-IP Install/Upgrade(all modules)

Known Affected Versions:
13.0.0, 13.0.0 HF1, 13.0.0 HF2, 13.0.0 HF3, 13.0.1, 13.1.0,,,,,,,,, 13.1.1,,,,, 14.0.0,,,,,, 14.0.1,, 14.1.0,,,,,, 14.1.2,,,,, 15.0.0, 15.0.1,,

Fixed In:
15.1.0,,, 13.1.3

Opened: Apr 10, 2019
Severity: 3-Major


The system does not roll forward the FastL4 profile syn-cookie-enable attribute after upgrading from 12.x to 13.x and beyond.


If syn cookies are explicitly disabled on a FastL4 profile prior to upgrading, they may be enabled. FastL4 profiles with default values for "hardware-syn-cookie" (enabled) and "software-syn-cookie" (disabled) prior to upgrading will have "syn-cookie-enable" set to "disabled" on first boot after upgrading.


This happens when upgrading from 12.x to 13.x and beyond.


You can fix the configuration by modifying it manually after upgrading. In tmsh: tmsh modify ltm profile fastl4 <profile_name> syn-cookie-enable <enabled|disabled>

Fix Information


Behavior Change