Synchronize services in a Cluster environment

Question

Hi,

I have a service running in a clustered environment. This service talks to the database and performs some CRUD operations. At anytime only one of the services should perform CRUD operations. How can I achieve this in a clustered environment? (or how do I synchronize the service across the instances)

PS - Record locking on the database table is not an open option for me.

Thanks in advance.