Bug ID 476708: ZebOS using BGP ECMP may not correctly update the ECMP paths when one of the paths goes down and comes back up

Last Modified: May 29, 2024

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

Known Affected Versions:
11.3.0, 11.4.0, 11.4.1, 11.5.0, 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

Fixed In:
11.4.1 HF9

Opened: Aug 25, 2014

Severity: 3-Major

Related Article: K34225935

Symptoms

ZebOS using BGP equal-cost multi-path routing (ECMP) might not correctly update the ECMP paths when one of the paths goes down and comes back up.

Impact

ECMP does not function as desired because both available paths are not utilized. This can only be recovered by clearing the BGP connection on the affected ECMP path.

Conditions

This occurs when a downstream ECMP link is disabled such that one of the two equal-cost paths becomes unavailable, and is then enable.

Workaround

None.

Fix Information

Correctly update the ECMP route paths on update.

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips