Backing up an application server

To protect an application server, create a backup plan or use the Backup now feature as described in the "Backup" section.

Applications that use databases require a few simple measures to ensure the application data consistency within a disk backup.

Databases may be stored on more than one disk or volume. To ensure that all necessary files are included in a backup, back up the entire machine. This also ensures that the application will remain protected if you add more databases or relocate the log files in the future.

If you are sure that the databases and their associated files are always on the same volumes, you may want to back up only these volumes. Or you may want to create separate backup plans for the system volume and for the volumes that store the data. In both cases, make sure that all of the volumes containing the necessary files are included in the backup. For instructions on how to find out the database paths, refer to "Locating database files".

If the application databases are located on a number of machines, back up all of the machines on the same schedule. For example, include all of the SQL servers belonging to a SharePoint farm in a centralized backup plan running on a fixed schedule.

Microsoft Volume Shadow Copy Service (VSS) should be used to ensure consistency of the database files in the backup. Without VSS, the files would be in a crash-consistent state; that is, after the recovery, the system would be in the same state as if the power were disconnected at the moment when backup began. While such backups are good enough for most applications, applications that use databases may not be able to start from a crash-consistent state.

A VSS provider notifies VSS-aware applications that the backup is about to start. This ensures that all database transactions are completed by the time Acronis Backup takes the data snapshot. This, in turn, ensures the consistent state of the databases in the resulting backup.

Acronis Backup can use various VSS providers. For Microsoft products, Microsoft Software Shadow Copy Provider is the best choice.

On a physical machine, using VSS is configurable. This also applies to a virtual machine that is backed up from inside the guest OS. You may need to enable using VSS manually if the factory preset was changed from the default value.

You also need to make sure that VSS writers for the respective application are turned on. In Windows Small Business Server 2003, the Exchange writer is turned off by default. For instructions on how to turn it on, see the following Microsoft Knowledge Base article http://support.microsoft.com/kb/838183/.

To enable using VSS by default in any backup plan created on a machine:

Connect the console to the machine.
On the top menu, select Options > Default backup and recovery options > Default backup options > Volume Shadow Copy Service.
Click Use Volume Shadow Copy Service.
In the Snapshot provider list, click Software - System provider.

When the console is connected to the management server, you can set the same default setting for all of the registered machines.

When backing up a virtual machine at a hypervisor level, using VSS is not configurable. VSS is always used if VMware Tools or Hyper-V Integration Services are installed in a respective guest system.

Installing these tools/services is a common requirement for backing up at a hypervisor level. If you encounter errors mentioning "quiesced snapshot" when backing up ESX(i) virtual machines, then reinstalling or updating VMware Tools and rebooting the virtual machine will usually help. For more information, see http://kb.acronis.com/content/4559.

Active Directory normally uses circular logging. Logs of other VSS-aware applications (except for Microsoft SQL Server) can be truncated by using the Enable VSS Full backup option. This option is effective on a physical machine and on a virtual machine where Agent for Windows is installed.