Bug ID 559554: CHD congestion control can have erroneous very large cwnd.

Last Modified: Jul 13, 2024

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

Known Affected Versions:
11.5.0, 11.5.1, 11.5.1 HF1, 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, 11.5.1 HF10, 11.5.1 HF11, 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, 11.5.4 HF2, 11.5.4 HF3, 11.5.4 HF4, 11.5.5, 11.5.6, 11.5.7, 11.5.8, 11.5.9, 11.5.10, 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, 11.6.1, 11.6.1 HF1, 11.6.1 HF2, 11.6.2, 11.6.2 HF1, 11.6.3, 11.6.3.1, 11.6.3.2, 11.6.3.3, 11.6.3.4, 11.6.4, 11.6.5, 11.6.5.1, 11.6.5.2, 11.6.5.3, 12.0.0, 12.0.0 HF1, 12.0.0 HF2

Fixed In:
12.1.0, 12.0.0 HF3

Opened: Nov 23, 2015

Severity: 3-Major

Symptoms

At times, CHD congestion control can store a very large congestion window, resulting in release of data well beyond that warranted by network conditions.

Impact

Possible network congestion.

Conditions

The client advertises a receive window less than 1 MSS, and CHD tries to decrease the window.

Workaround

Change congestion control algoirhtm from CHD.

Fix Information

This fix checks the bounds on the congestion window when CHD congestion control is enabled.

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips