Bug ID 421964: One-way packet loss on a LACP-enabled link and link aggregation

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, 11.5.3, 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

Fixed In:
11.6.0

Opened: May 28, 2013

Severity: 3-Major

Related Article: K15964

Symptoms

When there is one-way packet loss on a LACP-enabled link, the packet-loss side BIG-IP system still aggregates the LACP link.

Impact

Unidirectional packet loss causes only one unit to remove link from LACP aggregation

Conditions

LACP configured.

Workaround

None.

Fix Information

BIG-IP system now correctly aggregates an LACP-enabled link.

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips