Bug ID 461587: TCP connection can become stuck if client closes early

Last Modified: Apr 10, 2019

Bug Tracker

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

Known Affected Versions:
10.2.2, 10.2.4, 11.2.1, 11.3.0, 11.4.0, 11.4.1, 11.5.0, 11.5.1, 11.5.1 HF1, 11.5.1 HF10, 11.5.1 HF11, 11.5.1 HF2, 11.5.1 HF3, 11.5.1 HF4, 11.5.1 HF5, 11.5.1 HF6, 11.5.1 HF7, 11.5.1 HF8, 11.5.1 HF9, 11.5.2, 11.5.2 HF1

Fixed In:
11.6.0, 11.5.3, 11.4.1 HF9, 10.2.4 HF8

Opened: May 09, 2014
Severity: 3-Major
Related AskF5 Article:
K15973

Symptoms

Connection remains half-open and appears in connflow table after receiving FIN/ACK from serverside. the BIG-IP system never sends FIN/ACK to serverside to indicate connection has been closed.

Impact

Connection remains half-open and stuck in connflow table

Conditions

Clientside connection is closed before serverside completes 3-way handshake. Serverside never completes 3-way handshake and LB::reselect command is issue via iRule.

Workaround

None

Fix Information

Serverside connections established due to LB::reselect will now correctly get closed after the 3-way handshake completes if the corresponding clientside connection has already been closed.

Behavior Change