SharePoint 2010 Command Line Backup and Restore: Granular Backup and Restore via PowerShell

The Export-SPWeb cmdlet exports the contents of a web or list within a web to one or more files, as shown in the example that follows:

Export-SPWeb - Identity http://foo/sites/bar/site1 -Path c:\backups\site1.cmp


					  

Get-SPWebApplication -identity $URL | Get-SPSite -filter {$_.Owner = $siteOwner} | Get-
SPWeb | Export-SPWeb -path $backupStorage


					  

The items in the list that follow describe the various parameters that can be used to call Export-SPWeb to export or create a granular backup of a SharePoint site, one or all of its subsites, or a list within a site:

• Identity. When you export a web or a list within a web, this parameter is required and must be a valid URL or GUID for the target item.

• Path. When you export a web or a list within a web, this parameter is required and must be a valid UNC or Windows directory path to a file that the backup is saved in. The account logged into the SharePoint 2010 Management Shell must have permission to write to the directory specified for this input.

• AssignmentCollection. This is an optional parameter, intended to allow for the proper disposal of objects. Carefully consider using this parameter if your call of Export-SPWeb also involves using SharePoint’s SPWeb, SPSite, or SPSiteAdministration objects; otherwise, it is not likely to be necessary.

• CompressionSize. This parameter is not required. If used, it indicates the maximum size that the compressed export files are allowed to be created to and allows you to set a preferred target size for the CAB files (typically saved as files with a .cmp extension) created by the operation. If the total size of the export is greater than that amount, it is automatically broken into multiple files.

• Confirm. This is an optional parameter. If this parameter is used with an input value of True, the cmdlet prompts the user to confirm that he wants to proceed with the action. If a value of False is provided, the cmdlet proceeds without prompting for permission once executed. The default value for this parameter is False.

• Force. This is an optional parameter that does not actually require an input value to be provided for it. If this switch is not used, the cmdlet does not proceed with the backup operation if it estimates that there is not enough disk space available to store the backup. If it is used, that check is overridden, and the backup is executed regardless of how much storage is available.

• Item. This parameter is not required. It sets the URL of the Web application, GUID, or object to be exported and must be a valid SharePoint URL within the farm. When using this parameter, the full address of the target item is not required. For example, if you are targeting the subsite bar within the http://foo site collection, you would provide /bar for this parameter. Targeting the Calendar list within that bar subsite would be /bar/Lists/Calendar. Of course, you could also use the GUID for each of these items to specify them.

• HaltOnError. This input parameter is not required; if it is included, the export process is stopped and not completed if errors are encountered.

• HaltOnWarning. This input parameter is not required; if it is included, the export process is stopped and not completed if warnings are encountered.

• IncludeUserSecurity. This input parameter is not required; if it is included, the export process includes the user security settings of the targeted item in the export files.

• IncludeVersions. This input parameter is not required; if it is included, the export process includes the versioning data of the targeted item in the export files based on the type of file or list item history provided as a parameter. If no value is provided for this parameter, a default value of 1 is used to export the target’s last major version, which can also be targeted with a value of LastMajor. You can use this parameter to target the most current version (major or minor) using a value of CurrentVersion or 2, both the last major and minor versions for the item with a value of LastMajorandMinor or 3, or all versions for the targeted item with a value of All or 4.

• NoFileCompression. This input parameter is not required; if it is included, the export process does not compress the export files it creates. Using this parameter does create a simple problem if you do not direct the export to its own directory. Because the files are not compressed, they are not contained in a CAB file. For performance reasons, Microsoft recommends compressing the export files; their research shows that compression reduces the completion time for export processes by up to 30 percent. If this parameter is used during an export operation, it must also be used during an import operation using the export files it creates.

• NoLogFile. This input parameter is not required; if it is included, the export process does not create a log file for the export process. It should only be used to improve performance of the export process in extreme conditions; in most circumstances, a log file is desired for export operations.

• UseSQLSnapshot. This input parameter is not required; when you use it, Export-SPWeb creates a SQL Server database snapshot of the content database containing the targeted item. The export is created by referencing the snapshot rather than the database. Once the export is completed, the cmdlet deletes the database snapshot. You can only use this parameter if your SQL Server instance supports the creation of database snapshots. That’s why it is important to review your SQL Server edition prior to using it. If your instance does support snapshots, this parameter is recommended because, unlike Backup-SPSite, the targeted site collection is not automatically locked during the operation. Unless you manually take action to set the target to read only, your users can modify it during the export process. Because the cmdlet is reading from the snapshot and not the database, there is a drastically reduced chance of resource contention between it and the activities of your users.

• WhatIf. This is an optional parameter. If you use this parameter, PowerShell displays a message stating what the outcome of running the cmdlet will be, but the cmdlet itself is not executed. This can be helpful when testing scripts, allowing you to verify that you can provide the correct set of inputs and parameters to the cmdlet.

Import-SPWeb

Import-SPWeb is the flip side of the Export-SPWeb’s coin; it imports the contents of exports created with Export-SPWeb back into a SharePoint 2010 environment. The example that follows shows an import operation that imports both the content and the version data contained in the export file and overwrites any SharePoint content already existing in the target location:

Import-SPWeb -Identity http://foo/sites/bar/site1 -Path c:\backups\site1.cmp
-UpdateVersions -Overwrite


					  

• Identity. When you import a web or a list within a web, this parameter is required and must be a valid URL or GUID for the target item that the export is imported into.

• Path. When you import a web or a list within a web, this parameter is required and must be a valid UNC or Windows directory path to the file or files to be imported. The account logged into the SharePoint 2010 Management Shell must have permission to read to the directory specified for this input.

• AssignmentCollection. This is an optional parameter, intended to allow for the proper disposal of objects. Carefully consider using this parameter if your call of Import-SPWeb also involves using SharePoint’s SPWeb, SPSite, or SPSiteAdministration objects; otherwise, it is not likely to be necessary.

• ActivateSolutions. This parameter is not required. If used, it indicates that any user solutions should be activated as part of the import process.

• Confirm. This is an optional parameter. If this parameter is used with an input value of True, the cmdlet prompts the user to confirm that he wants to proceed with the action. If a value of False is provided, the cmdlet proceeds without prompting for permission once executed. The default value for this parameter is False.

• Force. This is an optional parameter that does not actually require an input value to be provided for it. Using it instructs Import-SPWeb to overwrite any existing item matching the value of the Identity parameter.

• HaltOnError. This input parameter is not required; if it is included, the import process is stopped and not completed if errors are encountered.

• HaltOnWarning. This input parameter is not required; if it is included, the import process is stopped and not completed if warnings are encountered.

• IncludeUserCustomAction. This input parameter is not required; if it is included, the import process includes the user custom actions of the targeted item in the import files.

• IncludeUserSecurity. This input parameter is not required; if it is included, the import process includes the user security settings of the targeted item in the import files.

• UpdateVersions. This input parameter is not required; if it is included, the import process uses it to determine how version data in the imported file is integrated into existing versions in the target item. If no value is provided for this parameter, a default value of 1 is used to import the version data as a new version, which can also be accomplished with a value of Append. You can also use this parameter to overwrite the target item with a value of Overwrite and all its existing versions with the newly imported item, or you can ignore any existing files in the targeted location with a value of Ignore.

• NoFileCompression. This input parameter is not required; if it is included, the import process does not compress the import files it creates. For performance reasons, Microsoft recommends compressing the import files. Their research shows that it reduces the completion time for import processes by up to 30 percent. If you use this parameter during an export operation, you must also use it during any import operation using the export files it creates.

• NoLogFile. This input parameter is not required; if it is included, the import process does not create a log file for the import process. It should only be used to improve performance of the import process in extreme conditions; in most circumstances, a log file is desired for import operations.

• WhatIf. This is an optional parameter. If you use this parameter, PowerShell displays a message stating what the outcome of running the cmdlet will be, but the cmdlet is not executed. This can be helpful when testing scripts, allowing you to verify that you can provide the correct set of inputs and parameters to the cmdlet.