Introduction to the filer's commands for copying volumes
Purposes of the vol copy command set
The vol copy command set enables you to copy one volume to another. The commands in this command set control copying both data in the active file system and data in snapshots from one volume to another. The source and destination volumes of the copy can reside on the same filer or on different filers.
For more information about snapshots, see Chapter 11, "Snapshots."
When to copy volumes
The following table describes some situations where you might find copying volumes useful.
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Situation
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Reasons for copying one volume to another
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You want to copy data from one filer to another regularly to ensure high data availability.
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After you copy the data, clients can switch to the destination filer in the following scenarios:
- When you shut down the source filer for software or hardware upgrades.
- If a network client process accidentally deletes a large number of files on the source filer, clients can continue to have access to the files when you are restoring the files to the source filer.
- If the source filer is not available for reasons such as natural disasters, you can put the destination filer on-line to continue file service.
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You want to migrate data from one filer to another.
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The destination filer has more storage or is a model that supports newer technology, such as FC-AL disks.
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You want to move a volume from one set of disks to another on the same filer.
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Example
You can copy the vol0 volume to the vol1 volume and then delete duplicated files and directories in these volumes so that the original contents of vol0 are split into two volumes.
Example
You have eight 4-GB disks for the vol0 volume and four 9-GB spare disks. You can migrate vol0 to the four 9-GB disks and replace all 4-GB disks with larger capacity disks.
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Benefits of the vol copy command set
Although you can copy data on the filer using client programs such as cpio or using the filer's dump and restore commands, the vol copy command set offers the following benefits:
- When a vol copy command reads and writes data, the filer does not traverse directories on the filer. Data is copied block for block directly from the disks, which means that the filer can finish the copying faster than it could with other methods.
- Using a vol copy command, the filer preserves the snapshot data of the source volume. If, in the future, users might need to use snapshots that were taken before data was copied from one volume to another, for example, if users accidentally delete files and need to recover them, use a vol copy command for migrating data.
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reserved.
Part No. 210-02334
File: volcopy1.htm
Last updated: 04/26/99 08:11:53