Bug ID 2162197: After a controller upgrade, out-of-sync etcd processes can lead to unhealthy cluster

Last Modified: Jan 16, 2026

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

Known Affected Versions:
F5OS-C 1.8.2

Opened: Nov 25, 2025

Severity: 2-Critical

Symptoms

After a controller upgrade, is is possible that the controller etcd processes can be out of sync causing the cluster to go into an unhealthy state.

Impact

The cluster will remain in an unhealthy state.

Conditions

The etcd processes require a quorum of three and the third etcd process is not being launched which leaves the etcds on both controllers in an inconsistent state.

Workaround

On the active controller, manually launch the third etcd instance, by running this command at the root shell /etc/etcd/launch_etcd.sh Then issue a controller failover.

Fix Information

None

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips