Bug ID 1204481: System may flap external links multiple times during startup or links may fail to come up at all

Last Modified: Dec 07, 2023

Affected Product(s):
F5OS F5OS(all modules)

Fixed In:
F5OS-A 1.5.0, F5OS-A 1.4.0, F5OS-A 1.3.2

Opened: Dec 02, 2022

Severity: 2-Critical

Related Article: K000132166

Symptoms

When the system boots up, the interfaces may flap (go up and down) several times in quick succession before coming up and stabilizing. In some cases, the interfaces fail to come up at all. If a peer switch is configured to detect excessive link flaps, it may put the port in an err-disable state and prevent the link from coming up.

Impact

If the peer switch triggers a link-flap detection feature, the ports may remain offline until an administrator manually recovers the port on that switch.

Conditions

-- r5000 or r10000 Series appliance

Workaround

There is no workaround for this issue on the rSeries appliance. An administrator can mitigate this issue by doing one of the following: - configuring the peer switch to automatically try to recover ports that are disabled for excessive link flapping - increasing the number of link flaps required in a certain interval before the port is put in a disabled state

Fix Information

Disable sending of remote-fault signaling to peer device while the system is booting up.

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips