Secondary Copy
With a backup job, you can choose to run a Phase 2 job to create a Secondary Copy, which can be used for off‑site storage and disaster recovery purposes. NetVault provides two methods to create a Secondary Copy: Duplicate and Data Copy.
The Duplicate method creates an exact copy which is linked to the original backup. This method breaks down the backup into segments and copies the segments to the storage device. During restore, the segments from the primary backup and secondary copy are interchangeable. As it is not possible to mix unencrypted segments with encrypted segments during restore, you cannot enable or disable encryption for the Duplicate. If the original saveset is encrypted, the Duplicate method creates an encrypted copy. If the original saveset is not encrypted, this method creates an unencrypted copy.
The Data Copy method breaks down the backup into segments and copies the segments to the backup device. During restore, either the primary backup or the secondary copy is used to recover data; the segments from the primary backup and secondary copy are not interchangeable. Therefore, it is possible to enable encryption for the Data Copy when the primary copy is unencrypted. This option is useful when you want to use the deduplication option for primary backups.
The Data Copy job has two requests: one for read and another for write. When you set a priority to the Data Copy job, the first request (source request) receives the priority that the user assigns to it; the subsequent request (destination request) served as first priority in the background with priority 0 or 1. This implementation is to avoid waiting for the destination media request to be served if the source media is available.
Snapshot-based backups
On supported Windows platforms, NetVault plug-ins can use a hardware or software VSS provider to create consistent point-in-time copies of volumes, and use these snapshots to perform backups. The plug-ins can also create persistent snapshots, which can be used for data recovery operations.
Currently, the NetVault Plug-in for FileSystem supports snapshot-based backups.
There are multiple ways in which you can configure the plug-in to perform VSS-based backups. You can configure the plug-in to:
To create and use persistent snapshots, the data that you want to back up must reside on supported disk arrays. For more information about OS versions, plug-in versions, and disk arrays that support persistent snapshots, see the Quest NetVaultCompatibility Guide.
Backup retirement
A backup can be retained indefinitely or retired after a specified period. NetVault supports generation- and time-based retirement methods for backups. When a backup is retired, its index is deleted from the NetVault Database.
You can specify generation- and time-based retirement methods for backups:
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Generation-based backup retirement: This method specifies the maximum generation count for a Full Backup (that is, the maximum number of Full Backups that are retained for the same data set). Generation-based retirement can only be set for Full Backups. When the number of Full Backups exceeds the specified generation count, the oldest Full Backup is retired. |
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Time-based backup retirement: This method specifies the length of time a backup is retained. You can specify the retirement age for backups in number of days, weeks, or years. A backup is retired when the retirement age is reached. Time-based retirement can be set for all backup types (that is, Full, Incremental, and Differential). |
If a backup has any dependent backups, you can use the following rules to delete the backup series:
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Retire all backups when the last backup is retired: By default, the retirement of a backup series is deferred until all backups from this series are ready for retirement. The backups from an Incremental series or a Differential series are retired when the last dependent backup from the series is retired. |
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Retire all backups when the first backup is retired: NetVault lets you modify the retirement behavior to retire a backup series when the first backup is retired. When this rule is applied, the backups from an Incremental series or a Differential Series are retired when the first backup from the series is retired. |
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Use the Retirement Timing Control settings to change the default behavior for all backups |
The following examples illustrate the retirement behavior for different backup series:
In this example, Full Backups are performed on Sunday and Incremental Backups are performed from Monday through Saturday. The retention period is set to seven days.
The Incremental Backups depend on the most recent backup of any type (Full, Incremental, or Differential). Therefore, these backups create a single backup series:
Full Backup <- Incremental Backup 1 <- Incremental Backup 2 <- Incremental Backup 3 <- Incremental Backup 4 <- Incremental Backup 5 <- Incremental Backup 6
Depending on the retirement rule that is applied, the backups are retired as follows:
In this example, Full Backups are performed on Sunday and Differential Backups are performed from Monday through Saturday. The retention period is set to seven days.
Differential Backups depend on the recent Full Backup. Therefore, these backups create six separate backup series:
Full Backup <- Differential Backup 1
Full Backup <- Differential Backup 2
Full Backup <- Differential Backup 3
Full Backup <- Differential Backup 4
Full Backup <- Differential Backup 5
Full Backup <- Differential Backup 6
Depending on the retirement rule that is applied, the backups are retired as follows:
In this example, Full Backups are performed on Sunday, Incremental Backups are performed on Monday, Tuesday, and Thursday, and Differential Backups are performed on Wednesday and Saturday. The retention period is set to seven days.
The Differential Backups depend on the recent Full Backup, while the Incremental Backups depend on the most recent backup of any type (Full, Differential, or Incremental). Therefore, these backups create three separate backup series:
Full Backup <- Incremental Backup 1 <- Incremental Backup 2
Full Backup <- Differential Backup 1 <- Incremental Backup 3 <- Incremental Backup 4
Full Backup <- Differential Backup 2
Depending on the retirement rule that is applied, these backups are retired as follows:
About NetVault Sets
NetVault Sets are used to create backup and restore jobs.
You can use sets to store data selections, backup and restore options, scheduling options, device and media options, and other advanced backup and restore options. Sets eliminate the need to manually select the data items or configure backup and restore options for each job, and allow you to quickly and easily apply the same data selections and options to multiple jobs.
For example, you can save the data selections in a Backup Selection Set, and use this set to create Full, Incremental, and Differential Backup jobs to ensure that the same data set is used for all jobs. Similarly, you can change the day, date, or time in a Schedule Set to automatically change the job schedule for multiple jobs, or specify a new device for backups by changing the Target Set.
The following table describes the set types that are available in NetVault.
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Backup Selection Set |
This set is used to specify data selections for backup jobs. The data items that are available for selection depend on the plug-in in use.
For more information about these sets, see the relevant plug-in user's guide. |
Plugin Options Set |
This set is used to specify the backup method, backup type, and other backup options.
The backup options that are available to a job depend on the plug-in in use. For more information about these sets, see the relevant plug-in user's guide. |
Schedule Set |
This set is used to specify scheduling options for backup and restore jobs. These options define when and at what intervals a job runs.
NetVault includes the following predefined Schedule Sets:
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Source Set |
This set is used to specify source device options.
A Source Set is required for the following jobs:
NetVault includes the following predefined Source Set:
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Target Set |
This set is used to specify target device and media options for backup jobs.
NetVault includes the following predefined Target Sets:
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Backup Advanced Options Set |
This set is used to specify backup retirement settings, Secondary Copy job definitions, user-defined events, and other advanced options.
NetVault includes the following predefined Backup Advanced Options Sets:
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Restore Selection Set |
This set is used to specify data selections for restore jobs.
The data items that are available for selection depend on the plug-in in use. For more information, see the relevant plug-in user's guide. |
Restore Advanced Options Set |
This set is used to specify restore type, user-defined events, and other advanced restore options.
NetVault provides the following predefined Restore Advanced Options Set:
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