Bug ID 551925: Misdirected UDP traffic with hardware acceleration

Last Modified: Sep 13, 2023

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

Known Affected Versions:
11.4.1, 11.5.0, 11.5.1, 11.5.2, 11.5.3, 11.5.4, 11.5.5, 11.5.6, 11.5.7, 11.5.8, 11.5.9, 11.5.10, 11.6.0, 11.6.1, 11.6.2, 11.6.3, 11.6.3.1, 11.6.3.2, 11.6.3.3, 11.6.3.4, 12.0.0, 12.0.0 HF1, 12.1.0 HF1, 12.0.0 HF2, 12.1.0 HF2, 12.0.0 HF3, 12.0.0 HF4, 12.1.1 HF1, 12.1.1 HF2, 12.1.2 HF1, 12.1.2 HF2, 12.1.0, 12.1.1, 12.1.2, 12.1.3, 12.1.3.1, 12.1.3.2, 12.1.3.3, 12.1.3.4, 12.1.3.5, 12.1.3.6, 13.0.0, 13.0.0 HF1, 13.0.0 HF2, 13.0.0 HF3, 13.0.1, 13.1.0, 13.1.0.1, 13.1.0.2, 13.1.0.3, 13.1.0.4, 13.1.0.5, 13.1.0.6, 13.1.0.7, 13.1.0.8, 13.1.1, 14.0.0, 14.0.0.1, 14.0.0.2, 14.0.0.3, 14.0.0.4, 14.0.0.5, 14.0.1, 14.0.1.1

Fixed In:
14.1.0, 13.1.1.2, 12.1.3.7, 11.6.4

Opened: Oct 11, 2015

Severity: 3-Major

Symptoms

UDP traffic might be forwarded to the wrong destination when using hardware acceleration.

Impact

Traffic can be sent to the wrong destination.

Conditions

If the UDP timeout is lower than the embedded Packet Velocity Acceleration (ePVA) aging timeout. This occurs because UDP connections are accelerated until the ePVA aging timeout expires for the connection. If the ePVA aging timeout is greater than the UDP timeout, then TMM removes the connection from software, but the connection is still accelerated in the ePVA. Subsequent traffic then matches to the original connection, causing it to be sent to the wrong destination.

Workaround

You can use either or both of the following workarounds: -- Increase the UDP timeout (60s or more). -- Disable UDP hardware acceleration.

Fix Information

None

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips