Bug ID 1132485: Controller sync can enter an erroneous double standby configuration in rare circumstances

Last Modified: May 29, 2024

Affected Product(s):
F5OS Install/Upgrade, Velos(all modules)

Known Affected Versions:
F5OS-C 1.5.0

Fixed In:
F5OS-C 1.6.0, F5OS-C 1.5.1

Opened: Jul 27, 2022

Severity: 2-Critical


Under rare circumstances, the controller sync daemon (which is responsible for mirroring data between active and standby controllers) can end up in a "double standby" configuration. This results in an interruption in proper controller synchronization, and can result in negative impacts such as controller software import or upgrade failure.


Controller sync does not work until corrected, which can result in a number of negative side effects such as import and live upgrade failures.


Controller sync daemon on both active and standby controllers is configured to "standby" mode.


On the active controller, run: echo get_state | nc -U /var/ccsync.unix If output is "standby", run: echo stop | nc -U /var/ccsync.unix echo start_active | nc -U /var/ccsync.unix

Fix Information

Fixed intermittent issue where controller sync could enter an erroneous double standby configuration.

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips