Bug ID 633512: HA Auto-failback will cause an Active/Active overlap, or flapping, on VIPRION.

Last Modified: Mar 12, 2019

Bug Tracker

Affected Product:  See more info
BIG-IP TMOS(all modules)

Known Affected Versions:
11.5.1, 11.5.1 HF1, 11.5.1 HF10, 11.5.1 HF11, 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, 11.5.2, 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, 11.6.0, 11.6.0 HF1, 11.6.0 HF2, 11.6.0 HF3, 11.6.0 HF4, 11.6.0 HF5, 11.6.0 HF6, 11.6.0 HF7, 11.6.0 HF8, 11.6.1, 11.6.1 HF1, 11.6.1 HF2, 11.6.2, 11.6.2 HF1, 11.6.3, 11.6.3.1, 11.6.3.2, 11.6.3.3, 11.6.3.4, 12.0.0, 12.0.0 HF1, 12.0.0 HF2, 12.0.0 HF3, 12.0.0 HF4, 12.1.0, 12.1.0 HF1, 12.1.0 HF2, 12.1.1, 12.1.1 HF1, 12.1.1 HF2, 12.1.2

Fixed In:
13.0.0, 12.1.2 HF1

Opened: Dec 14, 2016
Severity: 3-Major
Related AskF5 Article:
K20160253

Symptoms

When a preferred device becomes available and takes over due to an Auto-Failback configuration, the takeover is not performed as a smooth handoff, but instead results in both devices becoming Active for the network failover timeout period (3 seconds).

Impact

Since both nodes are Active for (by default) 3 seconds, this may cause network traffic to be dropped or interrupted during the overlap interval. In addition, the Active/Active overlap may not resolve in favor of the preferred device. When this happens, the preferred device attempts to Auto-Failback again after the Auto-Failback expires, and the process repeats forever.

Conditions

This problem affects traffic groups on VIPRION systems configured with HA Order and Auto-Failback enabled.

Workaround

Do not configure Auto-Failback on VIPRION.

Fix Information

The devices perform a clean handoff during Auto-Failback, with no Active/Active overlap.

Behavior Change