Bug ID 487554: System might reuse TCP source ports too quickly on the server side.

Last Modified: Sep 13, 2023

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

Known Affected Versions:
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 HF1, 11.5.3 HF1, 11.5.3 HF2, 11.5.4 HF1, 11.5.4 HF2, 11.5.4 HF3, 11.5.4 HF4, 11.5.0, 11.5.1, 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, 11.6.4, 11.6.5, 11.6.5.1, 11.6.5.2, 11.6.5.3, 12.1.0 HF1, 12.1.0 HF2, 12.1.1 HF1, 12.1.1 HF2, 12.1.2 HF1, 12.1.2 HF2

Fixed In:
12.0.0, 11.6.0 HF5, 11.5.2

Opened: Oct 29, 2014

Severity: 3-Major

Related Article: K41581381

Symptoms

System might reuse TCP source ports too quickly on server side when dag hash is ip-only and sourceport mode is set to change.

Impact

Conflicting flows result in connections being reset.

Conditions

This occurs when the dag-cmp hash is ip-only, and the virtual server or PEM-forwarding endpoints sourceport mode is set to change. The BIG-IP system might reuse some TCP source ports on the server side.

Workaround

This issue has no workaround at this time.

Fix Information

In this release, reuse of TCP source ports is sequential, which eliminates the issue of TCP source ports being used too quickly on the server side.

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips