Bug ID 1636077: Adding an operationally DOWN interface to existing LAG causes traffic disruption on r2k/r4k

Last Modified: Jul 19, 2025

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

Known Affected Versions:
15.1.10, 15.1.10.2, 15.1.10.3, 15.1.10.4, 15.1.10.5, 15.1.10.6, 17.1.0, 17.1.0.1, 17.1.0.2, 17.1.0.3, 17.1.1, 17.1.1.1, 17.1.1.2, 17.1.1.3, 17.1.1.4, 17.1.2, 17.1.2.1, 17.1.2.2, 17.5.0

Fixed In:
17.5.1

Opened: Sep 03, 2024

Severity: 3-Major

Symptoms

When an operationally DOWN interface is added to an existing LAG interface, traffic flow to the tenant stops on r2k/r4k based appliances.

Impact

Traffic flow gets impacted and the system misses the packets routed onto the LACP trunk to where the LAG member was added.

Conditions

-- Interface is marked down -- Interface is added to an existing LAG interface

Workaround

Restart tmm on all tenants that are associated with the trunk.

Fix Information

None

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips