Bug ID 1023529: FastL4 connections with infinite timeout may become immune to manual deletion and remain in memory.

Last Modified: Sep 29, 2022

Bug Tracker

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

Known Affected Versions:
14.1.0, 14.1.0.1, 14.1.0.2, 14.1.0.3, 14.1.0.5, 14.1.0.6, 14.1.2, 14.1.2.1, 14.1.2.2, 14.1.2.3, 14.1.2.4, 14.1.2.5, 14.1.2.6, 14.1.2.7, 14.1.2.8, 14.1.3, 14.1.3.1, 14.1.4, 14.1.4.1, 14.1.4.2, 14.1.4.3, 14.1.4.4, 14.1.4.5, 14.1.4.6, 14.1.5, 14.1.5.1, 14.1.5.2, 15.1.0, 15.1.0.1, 15.1.0.2, 15.1.0.3, 15.1.0.4, 15.1.0.5, 15.1.1, 15.1.2, 15.1.2.1, 15.1.3, 15.1.3.1, 15.1.4, 15.1.4.1, 15.1.5, 15.1.5.1, 15.1.6, 15.1.6.1, 15.1.7

Opened: Jun 07, 2021
Severity: 3-Major

Symptoms

Command "tmsh show sys tmm-traffic" reports non-zero number of current connections but "tmsh show sys connection" shows nothing.

Impact

Connections that were supposed to be removed by aggressive sweeper but were waiting for completion of an iRule may end up in a state where they are not reported by "tmsh show sys connection." Because of this issue, these connections cannot be deleted manually using 'tmsh del sys connection", but remain in memory. Their presence can be confirmed by non-zero number of current connections shown by "tmsh show sys tmm-traffic". Because of the infinite timeout setting, they will not timeout by themselves either.

Conditions

-- A virtual sever with fastL4 profile with infinite timeout enabled and an iRule containing "after" command. Having "-periodic" argument makes the problem more prominent. -- Aggressive sweeper activated due to low memory conditions.

Workaround

N/A

Fix Information

None

Behavior Change