Creating a Disk Group for a Database

You can use the vxdg command or the graphical user interface (GUI) to create a new disk group. A disk group must contain at least one disk at the time it is created. You also have the option to create a shared disk group for use in a cluster environment.

Disks must be placed in disk groups before they can be used by VxVM. You can create disk groups to organize your disks into logical sets of disks.

When you place a disk under VxVM control, the disk is initialized. Initialization destroys any existing data on the disk.

Prerequisites

• Only disks that are online and do not belong to a disk group can be used to create a disk group.
• The disk group name must be unique in the host or cluster.
• Creating a disk group requires at least one disk.

Usage Notes

• For information on the vxdg command, see the vxdg(1M) manual page.
• In the GUI, if multiple disks are specified in the Disk Device(s) field and only one disk name is specified in the Disk Name(s) field, VxVM appends numbers to the disk name so that each disk name is unique within its disk group.
• New disks must be placed under VxVM control and then added to a dynamic disk group before they can be used for volumes. The Actions > Rescan command performs these tasks to prepare new disks for VxVM use.
• When you place a disk under VxVM control, the disk is initialized. Initialization destroys any existing data on the disk.
• Disks are automatically assigned a default name. Once a disk is under VxVM control, you can select Actions > Rename Disk in the GUI to change the disk name.

Usage Notes

• The disk group name must be unique.
• The new disk group must contain at least one disk.
• Only disks that are online and do not belong to another disk group can be used to create a disk group.

  To create a new disk group using the command line

Use the vxdg command as follows:

Example

To create a disk group named PRODdg on a raw disk partition, where the disk name PRODdg01 references the disk within the disk group:

  To create a new disk group using the GUI

1. Select the Disk Groups folder.
2. Select Actions > New Disk Group.

   The New Disk Group wizard welcome appears.

3. You can suppress the Welcome to Create New Disk Group page by selecting the Do not show this page next time checkbox.
4. Click Next to continue. The New Disk Group wizard appears. Enter the following information:

   Group name:	Enter a new disk group name in the Group Name field.
   Create cluster group	If the cluster feature is available, you can select the Create cluster group checkbox if the new disk group is to be used with clusters.
   Available disks: Selected disks:	Select which disks (from Available disks:) you want to include in the group. Make sure the disks you want to include are in the right pane of the window (Selected disks:). (Normally, you would add all the disks you want in the group at this point. However, you can always add more disks later with the Add Disk to Disk Group procedure.)
   Disk names:	Type in the names of any disks to be added that do not appear under Selected disks:.

5. When you have provided all the necessary information in the dialog box, click Next.
6. Click Next to add the disks.
7. The Organization principle screen now appears.
8. Click None, if you do not want to organize the disk group. Otherwise, click any of the other organization categories under Organize Disk Group By to create an ISP disk group (refer to Organizing Disk Groups).
9. If you choose an organization principle other than None, the Specify Pool Names screen appears. Specify the names for the Data pool and the Clone pool and click Next. You must specify the pool names in order to create the first storage pool for an ISP disk group.
10. The next screen confirms the disks you have selected. Click Finish to continue if you are satisfied with the disk selection. If you are not satisfied, you can click the <Back button to go back to the previous screen in order to modify your selections.
11. After clicking Finish, the new disk group will then appear under the Disks Groups node.