1.1.1. Data Replication and Data Sharing Between Real Servers
Since there is no built-in component in LVS clustering to share the same data between the real servers, the administrator has two basic options:
Synchronize the data across the real server pool
Add a third layer to the topology for shared data access
The first option is preferred for servers that do not allow large numbers of users to upload or change data on the real servers. If the cluster allows large numbers of users to modify data, such as an e-commerce website, adding a third layer is preferable.