Sybase IQ generally propagates DDL and DML changes to secondary servers, so you only need to synchronize a secondary server for certain server management actions.
The process that updates a secondary server with respect to the coordinator is called synchronization.
The multiplex automatically makes committed changes, including global schema changes, changes to data in IQ tables visible on all servers in the multiplex.
You only need to synchronize in the following situations:
While creating a new secondary server
Restoring the coordinator from backup
Restarting a secondary server that has been excluded or shut down for an extended time period
After running the coordinator in single-node mode
After adding a file to the IQ_SYSTEM_MAIN dbspace