Bug ID 706104: Dynamically advertised route may flap

Last Modified: Sep 13, 2023

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

Known Affected Versions:
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

Fixed In:
14.1.0, 13.1.1.4, 12.1.4

Opened: Feb 09, 2018

Severity: 3-Major

Symptoms

ZebOS may repeatedly add and delete the routes from protocol daemons. This may cause the protocol daemons to delete and re-advertise the default route.

Impact

Route flapping may cause instability in the network, including inability to reach the default network advertised by the BIG-IP.

Conditions

- Dynamic routing in use - Kernel routes redistributed into a routing protocol - Static route configure in TMOS - Route advertisement enabled on the virtual-address that's the same as the static route

Workaround

Since the static route will be redistributed in the same way as the virtual-address, there is no need to enable route-advertisement on the VIP virtual-address. Disabling this will resolve the problem. The problem will also be resolved by moving the route from tmsh into ZebOS. - In imish config mode, "ip route <route> <gateway>" - In tmsh, "delete net route <route>"

Fix Information

Configuring a static route in TMOS and enabling route-advertisement on the same virtual-address no longer causes route flapping in ZebOS.

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips