Bug ID 658574: An accelerated flow transmits packets to a stale (incorrect) destination MAC address.

Last Modified: Oct 17, 2023

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

Known Affected Versions:
11.5.1, 11.5.2, 11.5.3, 11.5.4, 11.5.5, 11.5.6, 11.5.7, 11.5.8, 11.5.9, 11.5.10, 11.6.0, 11.6.1, 11.6.2, 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, 12.0.0, 12.0.0 HF1, 12.1.0 HF1, 12.0.0 HF2, 12.1.0 HF2, 12.0.0 HF3, 12.0.0 HF4, 12.1.1 HF1, 12.1.1 HF2, 12.1.2 HF1, 12.1.2 HF2, 12.1.0, 12.1.1, 12.1.2, 13.0.0, 13.0.0 HF1, 13.0.0 HF2, 13.0.0 HF3, 13.0.1

Fixed In:
13.1.0, 12.1.3

Opened: Apr 14, 2017

Severity: 2-Critical

Related Article: K61847644

Symptoms

An accelerated flow can send to a stale destination MAC address after the ARP packet with the updated MAC address is received. Warning: disabling auto-lasthop is not enough when they want BIG-IP to use updated destination MAC address.

Impact

The BIG-IP system sends packets to a stale (incorrect) destination MAC address. In this case, the new MAC address is not updated for the accelerated flow and the flow will continue to send traffic using the original MAC address.

Conditions

A flow is accelerated with a destination MAC address that changes while the flow is accelerated.

Workaround

Disable HW acceleration. Prevent the downstream destination MAC address from changing. For example, if the downstream unit is a BIG-IP active/standby configuration, then use MAC masquerading to prevent the MAC address from changing.

Fix Information

None

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips