Bug ID 452454: A RST will not be forwarded for a IP forwarding Virtual server with a fastL4 profile with loose initialization configured as well as an idle timeout that is less than the server idle timeout value.

Last Modified: May 14, 2019

Bug Tracker

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

Known Affected Versions:
11.3.0, 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

Fixed In:
11.6.0, 11.5.2, 11.4.1 HF6

Opened: Mar 14, 2014
Severity: 3-Major
Related AskF5 Article:
K15968

Symptoms

A RST will not be forwarded for a IP forwarding Virtual server with a fastL4 profile with loose initialization configured as well as an idle timeout that is less than the server idle timeout value.

Impact

The RST packet will not be forwarded.

Conditions

There are two sets of conditions that lead to this issue: 1) The IP forwarding virtual server is associated with a FastL4 profile that has the following configuration: -- Loose Initiation option is enabled. -- Reset on Timeout is disabled. -- Idle Timeout value is less than server idle timeout. -- No SNAT. 2) The IP forwarding virtual server is associated with a FastL4 profile that has the following configuration: -- Loose Initiation option is enabled. -- Loose Close option is enabled. -- Idle Timeout value is set to Immediate.

Workaround

Configure the server idle timeout to be less than the fastL4 profile's idle timeout.

Fix Information

Forward RST packet for IP forwarding Virtual with fastL4 profile with loose initialization configured and an idle timeout that is less than the server idle timeout.

Behavior Change