Bug ID 527393: VIP with UDP protocol and fastL4 profile, SERVER_CONNECTED is not fired.

Last Modified: Oct 17, 2023

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

Known Affected Versions:
11.6.0, 11.6.1, 11.6.2, 11.6.3,,,,, 11.6.4, 11.6.5,,,, 12.0.0, 12.0.0 HF1, 12.1.0 HF1, 12.0.0 HF2, 12.1.0 HF2, 12.0.0 HF3, 12.0.0 HF4, 12.1.1 HF1, 12.1.1 HF2, 12.1.2 HF1, 12.1.2 HF2, 12.1.0, 12.1.1, 12.1.2, 12.1.3,,,,,,,, 12.1.4,, 12.1.5,,,, 12.1.6, 13.0.0, 13.0.0 HF1, 13.0.0 HF2, 13.0.0 HF3, 13.0.1

Opened: Jun 10, 2015

Severity: 4-Minor

Related Article: K72509101


For a VIP with UDP protocol and fastL4 profile, the SERVER_CONNECTED iRule event is triggered in 10.x, but not in 11.x/12.x.


Unable to run iRule commands in a server-side context when data goes from client to server. The SERVER_DATA event does not fire until data is returned from server (or not at all if the server does not return data). The LB_SELECTED is client-side.


This occurs when using the fastL4 profile and UDP.


Change VIP from fastL4 to standard.

Fix Information


Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips