Synchronizing Clocks on Machines Participating in the Server Cluster
Make sure that the clocks on all machines that host the nodes included in your server cluster are synchronized to within one second. If the clocks on different machines are not synchronized, use a time-synch service to synchronize them. For instructions on how to synchronize clocks on different machines, go to the NIST Internet Time Service (ITS) page of the National Institute of Standards and Technology (NIST) web site.