Bug ID 561433: TMM Packets can be dropped indiscriminately while under DoS attack

Last Modified: Nov 07, 2022

Bug Tracker

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

Known Affected Versions:
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, 11.5.10, 11.5.2, 11.5.2 HF1, 11.5.3, 11.5.3 HF1, 11.5.3 HF2, 11.5.4, 11.5.4 HF1, 11.6.0, 11.6.0 HF1, 11.6.0 HF2, 11.6.0 HF3, 11.6.0 HF4, 11.6.0 HF5, 11.6.0 HF6, 11.6.0 HF7, 11.6.0 HF8, 12.0.0, 12.0.0 HF1, 12.0.0 HF2, 12.0.0 HF3, 12.0.0 HF4

Fixed In:
12.1.0, 11.6.1, 11.5.4 HF2

Opened: Dec 04, 2015
Severity: 3-Major

Symptoms

When there is a loaded tmm that cannot consume packets fast enough, packets might be dropped while when AFM DoS flood mitigation is taking place.

Impact

Packets will be dropped indiscriminately.

Conditions

-- Loaded tmm that cannot consume packets fast enough. -- AFM DoS flood mitigation is taking place.

Workaround

None.

Fix Information

There is now a sys db tunable (sys db dos.scrubtime) which can be set to drop DoS attack packets in hardware more aggressively. This will prevent other non-attack packets from being dropped indiscriminately.

Behavior Change