HP LeftHand P4000 SAN Solutions - Manual (Page 153)

Disk Management) may show you have X amount of free space, and the CMC view may show
the Used Space as 100% used.
CAUTION: Some file systems support defragmenting which essentially reorders the data on the
block device. This can result in the SAN allocating new storage to the volume unnecessarily.
Therefore, do not defragment a file system on the SAN unless the file system requires it.
Changing the volume size on the server
CAUTION: Decreasing the volume size is not recommended. If you shrink the volume in the CMC
before shrinking it from the server file system, your data will be corrupted or lost.
When you increase the size of the volume on the SAN, you must also increase the corresponding
volume, or LUN, on the server side.
Increasing the volume size in Microsoft Windows
After you have increased the volume size on the SAN (see Changing the volume size (page 159) ),
you must next expand the Windows partition to use the full space available on the disk.
Windows Logical Disk Manager, the default disk management program that is included in any
Windows installation, uses a tool called Diskpart.exe to grow volumes from within Windows.
Diskpart.exe is an interactive command line executable which allows administrators to select and
manipulate disks and partitions. This executable and its corresponding documentation can be
downloaded from Microsoft if necessary.
NOTE: Do not use Windows Disk Management to increase volume size.
Follow the steps below to extend the volume you just increased in the SAN.
1. Launch Windows Logical Disk Manager to rescan the disk and present the new volume size.
2. Open a Windows command line and run diskpart.exe.
3. List the volumes that appear to this host by typing the command list volume.
4. Select the volume to extend by typing select volume # (where # is the corresponding
number of the volume in the list).
5. Enter extend to grow the volume to the size of the full disk that has been expanded.
Notice the asterisk by the volume and the new size of the volume. The disk has been extended
and is now ready for use.
All of the above operations are performed while the volumes are online and available to users.
Increasing the volume size in other environments
Environments other than Windows use alternative disk management tools, which use a utility called
Extpart.exe. The only major difference is that instead of selecting the volume number, as in
Diskpart.exe, you select the drive letter instead.
Changing configuration characteristics to manage space
Options for managing space on the cluster include the following:
•
Changing snapshot retention—retaining fewer snapshots requires less space
•
Changing schedules to snapshot a volume—taking snapshots less frequently requires less
space
•
Deleting volumes or moving them to a different cluster
Ongoing capacity management 153