Bug ID 2261481: Packet loss on a F5OS tenant when vlan-groups are in use

Last Modified: Apr 22, 2026

Affected Product(s):
F5OS F5OS-A, F5OS-C(all modules)

Known Affected Versions:
F5OS-C 1.8.2

Opened: Apr 02, 2026

Severity: 3-Major

Symptoms

On an F5OS tenant, there may be packet loss when vlan-groups are in use. This occurs due to high churn inside the FDB table due to MAC addresses being learned between different host ports resulting in temporary DLF drops while the MAC is learned on the new port.

Impact

Packet loss. Failing monitor probes.

Conditions

- BX520 blade - VLAN groups - A large amount of unique MAC addresses in the FDB table

Workaround

Monitor probe issues may be alleviated by creating a static FDB entry for the local admin bit flipped MAC address that TMM is egressing packets from.

Fix Information

None

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips