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Multiplexed restores are especially useful in the case of databases. Often database backup performance can be optimized by
multiplexing multiple sessions during the backup. However, many online database backup utilities require that if multiple
backup sessions were run in parallel, they must be restored in parallel. Therefore, to enable multiplexed database backups,
the backup product must support the multiplexed restore capability.
Figure 20: Muiltiplexed database restores.
Any restore requests of a multiplexed backup image that are submitted inside an administrator-defined time window may be
restored in parallel. For example, assume eight clients were multiplexed to a single tape during backup. If the restore of three
of those clients was requested inside the administrator defined time window (default: 30 seconds), all three clients would be
restored simultaneously.
Restoring to Alternative Clients
The administrator on the master server can direct restores for any client (administrator-directed restores) or give a user on
one client permission to browse and restore files that were backed up from another client. This feature is convenient, for
example, when a workstation is down and the user wants to restore backed up files to another workstation and continue
working. The administrator on the master server can also direct files from the master server to any client.
Server Independent Restores
NetBackup supports restores using a NetBackup server other than the server used to write the backup. This provides easier
access to data for restores in multi-server environments, and better failover and disaster recovery capabilities.
Restores in Multi-Server Environments
The server-independent restore feature of NetBackup greatly simplifies operations and improves timely access to data in
NetBackup master/media server storage domain environments, where storage devices (drives or robotics) may be connected
to any server in the storage domain or where a large library is shared between servers (see Figure 21). Server independent
restore applies to the following multi-server situations:
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