Create Snapshot Virtual Disk Wizard: Additional Information for Windows 2000 and Windows Server 2003 - Dynamic Disks
Use the following procedure when creating on a running Windows 2000 and Windows Server 2003, using . Failure to complete the steps listed might result in an inaccurate point-in-time image of the .
Snapshot virtual disks might be reused (for frequent or nightly backups), or may be created for one-time usage (for speculative change or upgrade testing). For instructions on how to reuse a disabled snapshot virtual disk, refer to Reusing Snapshot Virtual Disks.
Creating a Snapshot Virtual Disk
Use the following procedure to create a snapshot virtual disk.
Caution:Risk of application errors -- Windows operating systems traditionally support a Master Boot Record (MBR) disk partition format. 64-bit Windows Server 2003 supports the new GUID Partition Table (GPT) disk partition format. The 32-bit Windows Server 2003 and Windows 2000 operating systems do not support this new partition format and do not know how to properly access a GPT disk. When a source virtual disk mapped to a 64-bit Windows Server 2003 host is initialized with the GPT disk partition format, any snapshot virtual disks created of this source virtual disk must also be mapped to a 64-bit Windows Server 2003 host. If you map the snapshot virtual disk to a 32-bit Windows Server 2003 or Windows 2000 host, the operating system does not recognize the partition format of the snapshot virtual disk. Alternatively, you can initialize the source virtual disk on the 64-bit Windows Server 2003 host with the older MBR disk partition format, and any snapshots of that source virtual disk are accessible by other 32-bit Windows hosts.
Important: Snapshot virtual disks created on a host running Windows 2000 or Windows Server 2003, using dynamic disks, might not be mapped on the same host as the base virtual disks.
1
Start the storage management software.
The Enterprise Management Window is displayed.
2
Launch an by selecting Tools >> Manage Storage Array.
The Array Management Window is opened in a separate window.
3
Within the Logical View of the Array Management Window, select a , and create a snapshot virtual disk by using one of the following methods:
Create a snapshot virtual disk by using either the Script Editor or a command line interface on the host operating system. Type the following command, and press Enter:
create snapshotVirtual Disk
For command reference information on creating a snapshot virtual disk, refer to the Enterprise Management Window online help.
4
Disable the snapshot virtual disk by using one of the following methods:
Select Virtual Disk >> Snapshot >> Disable in the Array Management Window. For more information, see Disabling a Snapshot Virtual Disk.
Use either the Script Editor or a command line interface on the host operating system. Type the following command, and press Enter:
disableSnapshot virtual disk
For command reference information on disabling a snapshot virtual disk, refer to the Enterprise Management Window online help.
5
Assign a between the snapshot virtual disk and the host that will access the snapshot virtual disk. Define virtual disk-to-LUN mappings by using one of the following methods:
Important: Snapshots of Windows 2000 or Windows Server 2003 Dynamic Disks might not be mapped on the same host as the base virtual disks.
Storage Partitioning Wizard, which helps you to quickly define a single . It guides you through the major steps required to specify which host will access a virtual disk and the associated . For more information, see Using the Storage Partitioning Wizard.
Create a virtual disk-to-LUN mapping by using either the Script Editor or a command line interface on the host operating system. Type the following command, and press Enter:
create mapping virtual disk
For command reference information on creating a virtual disk-to-LUN mapping, refer to the Enterprise Management Window online help.
Important: Stop all I/O activity to the source virtual disk at this point (or data transfer suspended). This action ensures that an accurate point-in-time image of the source virtual disk is captured. Close all applications (including Windows Explorer) to ensure all I/O activity has been stopped.
6
Run the utility to flush all the write buffers from the new disk physical disk.
At the host prompt, type the following command, and press Enter:
SMrepassist -f <filesystem-identifier>
where <filesystem-identifier> is the physical disk letter assigned to the source virtual disk.
Example:
If the new disk physical disk (for the source virtual disk) was assigned physical disk letter "E," you would enter the command: SMrepassist -f e: and press Enter.
The write buffers for the disk physical disk are flushed.
7
In the storage management software, re-create the snapshot virtual disk by using one of the following methods:
Use either the Script Editor or a command line interface on the host operating system. Type the following command, and press Enter:
recreateSnapshot virtual disk
For command reference information on recreating a snapshot virtual disk, refer to the Enterprise Management Window online help.
Important: If I/O activity to the source virtual disk was stopped or data transfer was suspended, resume I/O activity to the source virtual disk at this time (or re-enable data transfer).
8
Run the utility (or operating system-specific utility) or reboot the host where the snapshot will be used. This will ensure that the host operating system recognizes the snapshot virtual disk.
After virtual disks have been created and virtual disk-to-LUN mappings have been defined, run the hot_add utility to ensure that the operating system is aware of the newly created virtual disks, without having to reboot the host. For information on which operating systems support the hot_add utility, refer to your
operating system-specific storage management software installation guide.
9
Run the utility to associate the with a host operating system and to ensure that the snapshot virtual disk is recognized by the host.
After virtual disks have been created and virtual disk-to-LUN mappings have been defined, run the SMdevices utility to ensure that the virtual disk name and the operating system storage array name (assigned by the operating system) correlate.
10
Open the dialog by selecting Start >> Settings >>Control Panel, double-clicking the Administrative Tools icon, and then double-clicking Computer Management. In the console tree under Storage, select Disk Management.
Select Start >> Run, type the following command, and press Enter:
compmgmt.msc
At a host prompt, type the following command, and press Enter:
compmgmt.msc
In the console tree under Storage, select Disk Management.
The Disk Management dialog is displayed with a graphical representation of all the physical disks connected to the host and their associated partitions.
11
Blink the disk and virtual disk definition that represents the snapshot virtual disk.
Note: The snapshot virtual disks LUNs are displayed with the disk type foreign.
12
Select the snapshot virtual disk LUNs, right-click and select Import Foreign Disks.
The Import Foreign Disks dialog is displayed.
13
Select the appropriate disk, and click OK.
The snapshot virtual disks and LUNs are imported.
14
Perform a manual re-scan to verify that the disk information is correct.
From the Disk Management main menu, select Action >> Rescan Disks.
15
In the Disk Management dialog, locate the disk and virtual disk definition that represents the snapshot virtual disk you re-created, and ensure that a new physical disk letter has automatically been assigned.
16
Use the snapshot virtual disk with your backup application (reusing a snapshot virtual disk), or for speculative change and upgrade testing (one-time usage).
After the snapshot virtual disk is no longer required, disable or delete the snapshot virtual disk.
If you disable the snapshot virtual disk instead of deleting it, you can retain the snapshot virtual disk and its associated . Then, when you must create a different snapshot of the same source virtual disk, you can re-create the disabled snapshot virtual disk. This takes less time than creating a new snapshot virtual disk and stops any reduction in performance that might occur if the snapshot virtual disk remains available.
For more information, see Disabling a Snapshot Virtual Disk and Deleting a Virtual Disk. For command reference information on disabling or deleting a snapshot virtual disk, refer to the Enterprise Management Window online help.
Reusing Snapshot Virtual Disks
Typically, after a snapshot virtual disk has been created, it is disabled until a new point-in-time image of the same source virtual disk is required. Use the following procedure to create a new point-in-time image of the same source virtual disk.
Important: Stop all I/O activity to the source virtual disk at this point (or data transfer suspended). This action ensures that an accurate point-in-time image of the source virtual disk is captured. Close all applications (including Windows Explorer) to ensure all I/O activity has been stopped.
1
Run the utility on the host where the snapshot virtual disk is mounted to flush all the write buffers from the new disk physical disk.
At the host prompt, type the following command, and press Enter:
SMrepassist -f <filesystem-identifier>
where <filesystem-identifier> is the physical disk letter assigned to the snapshot virtual disk.
The write buffers for the disk physical disk are flushed.
2
Disable the snapshot virtual disk by using one of the following methods:
Select Virtual Disk >> Snapshot >> Disable in the Array Management Window. For more information, see Disabling a Snapshot Virtual Disk.
Disable a snapshot virtual disk by using either the Script Editor or a command line interface on the host operating system. Type the following command, and press Enter:
disableSnapshot virtual disk
For command reference information on disabling a snapshot virtual disk, refer to the Enterprise Management Window online help.
3
Run the utility on the host where the source virtual disk is mounted to flush all the write buffers from the new disk physical disk.
At the host prompt, type the following command, and press Enter:
SMrepassist -f <filesystem-identifier>
The write buffers for the disk physical disk are flushed.
4
In the storage management software, re-create the snapshot virtual disk by using one of the following methods:
Recreate a snapshot virtual disk using either the Script Editor or a command line shell on the host operating system. Type the following command, and press Enter:
recreateSnapshot virtual disk
For command reference information on recreating a snapshot virtual disk, refer to the Enterprise Management Window online help.
Important: If I/O activity to the source virtual disk was stopped or data transfer was suspended, resume I/O activity to the source virtual disk at this time (or reenable data transfer).
5
If you are using any 32-bit version of Windows, go to step 6.
If you are using the 64-bit version of Windows Server 2003, perform the following steps:
a
Blink the disk and virtual disk definition that represents the snapshot virtual disk.The snapshot virtual disk LUNs are displayed with the disk type "Dynamic, Offline."
b
Select the snapshot virtual disk disk, and right-click, and select Reactivate Disk.
The disk status returns to "Dynamic, Online" and the file system on the snapshot virtual disk becomes visible to the host machine.
6
Use the snapshot virtual disk with your backup application (or another application).
7
After the snapshot virtual disk is no longer required, disable the snapshot virtual disk.
If you disable the snapshot virtual disk instead of deleting it, you can retain the snapshot virtual disk and its associated snapshot repository virtual disk. Then, when you need to create a different snapshot of the same source virtual disk, you can re-create the disabled snapshot virtual disk. This takes less time than creating a new snapshot virtual disk and stops any reduction in performance that might occur if the snapshot virtual disk remains available.
Caution: Risk of application errors -- Windows operating systems traditionally support a Master Boot Record (MBR) disk partition format. 64-bit Windows Server 2003 supports the new GUID Partition Table (GPT) disk partition format. The 32-bit Windows Server 2003 and Windows 2000 operating systems do not support this new partition format and do not know how to properly access a GPT disk. When a source virtual disk mapped to a 64-bit Windows Server 2003 host is initialized with the GPT disk partition format, any snapshot virtual disks created of this source virtual disk must also be mapped to a 64-bit Windows Server 2003 host. If you map the snapshot virtual disk to a 32-bit Windows Server 2003 or Windows 2000 host, the operating system does not recognize the partition format of the snapshot virtual disk. Alternatively, you can initialize the source virtual disk on the 64-bit Windows Server 2003 host with the older MBR disk partition format, and any snapshots of that source virtual disk are accessible by other 32-bit Windows hosts.