Last Modified: Jul 15, 2026
Affected Product(s):
F5OS F5OS-C, Install/Upgrade
Known Affected Versions:
F5OS-C 1.8.2
Fixed In:
F5OS v2.0.0
Opened: Jan 25, 2026 Severity: 2-Critical
After a rolling upgrade of the controller software, one of the controllers may incorrectly be removed from the OpenShift cluster. This leaves the OpenShift cluster in a state where there is only one leader node in the cluster.
If this occurs the affected controller will no longer be in the OpenShift cluster, so HA availability of the OpenShift cluster between the controllers will be compromised.
This can happen during a rolling upgrade due to a race condition on checking the status of the standby controller.
The workaround is to manually retrigger the addition of the removed controller to the Openshift cluster. If controller-1 was removed, on controller 2 the user would do a touch /var/omd/CONTROLLER1_REINSTALL If controller-2 was removed, on controller 1 the user would do a touch /var/omd/CONTROLLER2_REINSTALL
The race condition that led to the controller being incorrectly removed from the cluster has been fixed, so that a controller will no longer be removed from the cluster during rolling upgrade.