Achieve maximum low cost uptime with Exchange 2007 messaging system
Exchange 2007 the latest version of Microsoft Exchange includes some new major capabilities that offer low cost availability for your massaging infrastructure. Until now Exchange didn’t offer any capability that will assist in a data corruption scenario, In case of database corruption the Exchange administrator had to restore the entire database from backup, which could lead for long frustrating downtime.
Even if you have installed Exchange 2003 cluster services it will not do in case of data corruption since the Exchange database has a single copy on the cluster disks.
What’s new with Exchange 2007?
Exchange 2007 includes a capability that allows database replication based on log shipping.
You can replicate the Exchange 2007 database with all its data to another location and keep this data currant with log shipping. The name of the database replication technology called continues replication.
Exchange 2007 supports three types of continues replication:
Local continuous replication (LCR)
LCR – Local Continues Replication enable the administrator to replicate the Exchange database to another location on the same server, LCR lowers the total cost of ownership for Exchange 2007 by reducing the number of regular backups that are required for data protection. Although LCR does not eliminate the need to take backups (data backup are important to have if a disaster strikes), it does significantly reduce the need to take regular, daily full backups. LCR provides fast recovery with current data, as well as a single-server solution for transaction log copying and replaying. The recovery from database corruption is done in seconds.
Cluster continuous replication (CCR)
CCR is based on windows clustering and allow a replication of Exchange cluster data between cluster nodes. CCR enable you to achive the maximum 24/7 uptime with Microsoft cluster and two instances of the same database. CCR combines automatic management of redundancy and application-level data replication. CCR is a solution that can be deployed without 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 make sure that all log data on the active node is successfully copied to the passive node. Therefore, scheduled outages do not result in loss of data, even though replication occurs asynchronously.
Standby continuous replication (SCR)
With SCR, data can be replicated on a per-storage group basis to standby servers or clusters. The SCR target, whether a single mailbox server or a cluster, can be placed inside the primary datacenter or in a remote location, ready to be manually activated if the primary server or datacenter fails. This feature is available on Exchange 2007 Service Pack 1.
SCR offer low cost replication to an offsite environment for DRP or recovery scenarios.
Ronen Gabbay.