Cluster continuous replication (CCR) provides automatic management of redundancy in addition to application-level data replication. CCR can be deployed without exposing a single point of failure in a single data center or between two data centers. Transaction log replication is used to copy the databases and maintain the concurrency of the data among cluster nodes.
The scheduled outage functionality in CCR is designed to ensure that all log data on the active node is successfully copied to the passive node. Therefore, scheduled outages do not result in data loss, even though replication occurs asynchronously.
This clustering method is recommended for Entry Tier customers as well as customers who have not already made a significant investment in Storage Area Network (SAN) and traditional multi-node, "single copy" cluster equipment.