Bug ID 769817: BFD fails to propagate sessions state change during blade restart

Last Modified: Oct 16, 2023

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

Known Affected Versions:
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, 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, 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, 12.1.3, 12.1.3.1, 12.1.3.2, 12.1.3.3, 12.1.3.4, 12.1.3.5, 12.1.3.6, 12.1.3.7, 12.1.4, 12.1.4.1, 12.1.5, 12.1.5.1, 12.1.5.2, 13.0.0, 13.0.0 HF1, 13.0.0 HF2, 13.0.0 HF3, 13.0.1, 13.1.0, 13.1.0.1, 13.1.0.2, 13.1.0.3, 13.1.0.4, 13.1.0.5, 13.1.0.6, 13.1.0.7, 13.1.0.8, 13.1.1, 13.1.1.2, 13.1.1.3, 13.1.1.4, 13.1.1.5, 13.1.3, 13.1.3.1, 13.1.3.2, 13.1.3.3, 13.1.3.4, 14.0.0, 14.0.0.1, 14.0.0.2, 14.0.0.3, 14.0.0.4, 14.0.0.5, 14.0.1, 14.0.1.1, 14.1.0, 14.1.0.1, 14.1.0.2, 14.1.0.3, 14.1.0.5, 14.1.0.6, 14.1.2, 14.1.2.1, 14.1.2.2, 14.1.2.3, 14.1.2.4, 14.1.2.5, 14.1.2.6, 14.1.2.7, 14.1.2.8, 14.1.3, 15.0.0, 15.0.1, 15.0.1.1, 15.0.1.2, 15.0.1.3

Fixed In:
15.1.0, 15.0.1.4, 14.1.3.1, 13.1.3.5, 12.1.5.3, 11.6.5.1

Opened: Apr 05, 2019

Severity: 2-Critical

Symptoms

BFD fails to propagate sessions state change during blade restart.

Impact

The BFD session remains in the BFD sessions table and remains there until BGP session is timed out by hold the timer (90 seconds, by default). Dynamic routes, which are learnt via affected BGP session, remain in the routing table until the hold time is reached.

Conditions

-- On a chassis with multiple blades, several routing protocol sessions are established, (e.g., BGP sessions). -- BFD sessions are configured for each BGP session to sustain fast failover of BGP sessions. -- There is a BGP session that can be established only via specific blade and the corresponding BFD session of this BGP session is processed on the same blade. -- This blade is restarted (e.g., using the bladectl command) or experienced a blade failure.

Workaround

Change BGP hold time to reasonable lower value.

Fix Information

The affected BFD session is removed from the BFD table after blade reset during the period configured for this BFD session.

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips