Bug ID 644851: Websockets closes connection on receiving a close frame from one of the peers

Last Modified: Jul 13, 2024

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

Known Affected Versions:
12.1.0, 12.1.0 HF1, 12.1.0 HF2, 12.1.1, 12.1.1 HF1, 12.1.1 HF2, 12.1.2, 12.1.2 HF1, 12.1.2 HF2

Fixed In:
13.1.0, 12.1.3

Opened: Feb 14, 2017

Severity: 3-Major


Websocket connection should be closed once an endpoint has both sent and received a Close control frame. BIG-IP closes connection on receiving a close frame from peer and does not wait for close frame from other endpoint. This results in data sent in the other direction to be dropped.


One endpoint sends a Websocket Close control frame. Other endpoint continues sending data which is dropped by BIG-IP.


Websocket and HTTP profile are attached to the virtual.



Fix Information

Half-close of connection will be triggered instead of closing the connection entirely.

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips