Bug ID 497742: Some TCP re-transmits on translucent vlangroup skip bit-flip on source MAC address

Last Modified: Aug 19, 2026

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

Known Affected Versions:
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, 11.6.0, 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

Fixed In:
12.0.0, 11.5.3

Opened: Dec 19, 2014

Severity: 3-Major

Related Article: K16296

Symptoms

Some packets re-transmitted as part of a full-proxy, non-SNAT'd TCP virtual server on a translucent-mode vlangroup do not correctly have the translucent-mode bit-flip applied.

Impact

Egressing traffic with the source-MAC of another host can potentially lead to traffic loops.

Conditions

This occurs with a translucent vlangroup and full virtual server with no SNAT.

Workaround

Enable SNAT on the virtual server.

Fix Information

All TCP re-transmits have the proper source MAC address.

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips