Consider the following before implementing your Exchange protection strategy:
Exchange application backups are run using the Unitrends Windows agent. The Exchange server must be running the latest service packs prior to installing the Unitrends Windows agent. The following components must also be installed and running on the Exchange server:
• | Microsoft Exchange VSS Writer. If the Exchange VSS Writer is not installed or is not running, an error message displays. The Exchange VSS Writer must be running to continue the backup operation. |
• | Microsoft VSS Service. |
Unitrends protects all supported Microsoft configurations of Exchange. For a complete list of supported Exchange environments, see the Unitrends Compatibility and Interoperability Matrix. For Microsoft requirements, see these Microsoft articles:
• | Exchange 2003 system requirements |
• | Exchange 2007 system requirements |
• | Exchange 2010 system requirements |
• | Exchange 2013 system requirements |
The following configurations are recommended for optimal protection and recovery:
Recommendation |
Description |
Disable circular logging |
This enables you to run differential or incremental backups of Exchange. If you do not disable circular logging, only full backups are supported. See Circular logging setting for more information. |
Do not allow the physical or virtual machine hosting the Exchange server to be a domain controller |
This enables much simpler and faster Exchange restores since you will not first have to restore Active Directory on the same server. |
Make sure that the physical or virtual machine hosting the Exchange server is a member of a domain that has at least two domain controllers |
This enables faster recovery. Active Directory information is replicated if there is more than one domain controller, which means that if one domain controller fails the other can be used to recover missing transactions after the failed domain controller is restored. |
Separate transaction log files from the Exchange server database |
Exchange performs much more efficiently if the Exchange database and transaction logs are placed on different physical storage devices. In addition, by separating these two important components, recovery of failed storage is eased. |
Disable the write cache on any hard drive or RAID adapters being used in the system that is hosting the Exchange server |
This prevents data corruption by ensuring that any Exchange write operation is committed to secondary storage (i.e., disk) correctly. |
Consider the following when planning your Exchange protection strategy:
When you run asset-level backups of the Windows server hosting Exchange, certain Exchange-related files are automatically excluded. For example, all transaction log files (i.e., .LOG files), the Exchange database (i.e., .EDB files), and streaming content files (i.e., .STM files) are excluded.
Incremental backups can be used for Exchange versions 2007 or higher. Exchange incrementals offer the following benefits:
• | Incrementals can run more quickly and frequently than differentials since they include only the changes since the last successful full or incremental backup. This enables you to meet more aggressive RPOs than with differentials, which contain all changes since the last full backup. |
• | Upon completion of a successful incremental, unneeded transaction log files are automatically truncated, freeing space on the Exchange server. Automatic log truncation does not occur with Exchange differentials. |
When creating an Exchange job that includes incremental backups:
• | Differentials and incrementals cannot be in the same schedule. |
• | A full backup must be in the schedule. The incremental forever strategy is not supported. |
Circular logging is an Exchange feature that enables transaction log files to be overwritten. Unitrends recommends disabling circular logging. You must disable circular logging to run differentials or incrementals. If you enable circular logging, then the only type of backup that you can perform is a full. If circular logging is disabled, the transaction logs are used to perform differential or incremental backups.
• | With differentials, these transaction logs accumulate until a successful full backup runs. |
• | With incrementals, unneeded logs are removed after each successful backup. |
The removal of unneeded truncation logs is typically termed transaction log truncation. Transaction log truncation removes unneeded logs but does not reclaim space. Reclaiming space is a separate operation that must be performed periodically by the Exchange system administrator.
Unitrends leverages the Microsoft snapshot feature to protect Exchange. Our protection of Exchange with these snapshots is not supported for the following:
• | Any type of NAS configuration (SAN configurations are supported). |
• | The Exchange 2003 Recovery Storage Group feature. |
Unitrends protects databases and storage groups as follows:
• | Databases - For Exchange 2013 and 2010, you can back up multiple databases or a single database. |
• | Storage groups- For Exchange 2007 and 2003, you can back up multiple storage groups or an individual storage group. You cannot back up individual databases within a storage group. The reason for this is the transaction logs for the entire storage group are backed up for each database selected. Thus a full backup must be run on every database in a storage group in order for the transaction logs to be properly handled for full/differential backups. |
Additional requirements apply for Exchange CCR, SCR, and DAG environments. See the Unitrends Knowledge Base for details.