The Redundant clock failed message on a Catalyst 6000 series model indicates clock module failure. If the clock module fails, it is impossible to change from a primary clock to a standby clock.
The clocks are located on the chassis. To resolve this issue, find a hardware replacement for the clock module.
Perform one of these options:
For warranty service, contact the Cisco Technical Support directly at 1-800-553-2447 or online by using the TAC Service Request Tool.
If you have a hardware support contract directly with Cisco for this part, open a service request online by using the TAC Service Request Tool. After opening the service request use the Service Request Query Tool to request a replacement part directly.
If your product is not covered by contract or warranty, contact your Cisco partner or reseller to request a replacement part for the hardware component that is causing the issue.