Bug ID 1249825: PEM policy rules to modify HTTP headers may not be effective

Last Modified: Jul 12, 2023

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

Opened: Feb 21, 2023

Severity: 3-Major


When a PEM policy rule is configured with a 'Modify Header' action, the rule may not be effective if fast-pam ('Connection Optimization' in the GUI) is enabled. The desired header modification may work briefly, or on some subscriber flows, but not others, and may stop working entirely after configured changes are made to the policy rule. Note that this issue is specific to the 'Modify Header' action. If the rule is configured with other actions, those actions operate normally.


PEM policy rules that have an action to modify HTTP headers may not be effective.


- A pem policy rule is configured with the 'modify header' action - A fast-pem fastl4 virtual server is configured in the related pem profile (This is named 'Connection optimization' in the GUI)


Disable fast-pem (Connection optimization) in the PEM profile. Note that disabling fast-pem will result in a performance hit as the standard VIP will process all traffic, instead of the optimized fastl4 VIP.

Fix Information


Behavior Change

Guides & references

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