Bug ID 429699: Intra-VLAN bridging on 2x00 and 4x00 appliances may not work in conjunction with vlangroups on the standby box of an HA pair

Last Modified: Jul 12, 2023

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

Known Affected Versions:
11.2.0, 11.2.1, 11.3.0, 11.4.0, 11.4.1

Fixed In:

Opened: Sep 04, 2013

Severity: 3-Major

Related Article: K15141


Bridging traffic between two interfaces on a child VLAN in vlangroups mode may be disrupted when there are packets arriving on another child vlan of the same vlangroup that create conflicting FDB entries.


In active mode, the 2x00 and 4x00 boxes will preferentially bridge over the vlangroup rather than to another port on the child vlan. In standby mode, this remains true, but the frame gets dropped unless we are set to bridge in standby.


For this to happen, there usually has to be an unresolved loop in your network.


It is inadvisable to use the 2x00 and 4x00 platforms as a switch/bridge at this point. Having no hardware support the switching happens in software at a higher latency and CPU cost.

Fix Information

For translucent vlan groups, allow standby 2x00/4x00 in ha pair to use local vlan FDB entry for bridging the traffic between two interfaces on a child vlan in the given vlan group.

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips