Creating a Volume Resource Hierarchy

When you want to protect resources on shared SCSI disks, you partition the shared disk into logical volumes using the Windows Disk Management tool. LifeKeeper for Windows can protect shared volumes by defining a volume resource instance. Each instance is assigned a drive letter (for example, G:).

LifeKeeper for Windows brings the volume resource instance into service on the primary server and provides software locks so that a backup server cannot access the volume while it is active on the primary server. In case of a failure of the primary server, LifeKeeper for Windows automatically brings the volume resource into service on the backup server and locks the primary server from accessing the volume resource when it is repaired.

LifeKeeper for Windows also automatically changes the primary and designations so that the failed server is now locked from access to the volume resource. In this way, the resource is protected from inappropriate access while you repair the failed server.

This dynamic redefinition of primary and backup servers is LifeKeeper for Windows’ intelligent switchback feature that allows you to select the appropriate time to bring the resource back into service on the repaired system.

To create a volume resource, follow the steps below. Since LifeKeeper for Windows maintains the volume locks, do not stop LifeKeeper for Windows after creating the resource, as this would disable the locks.

*Before creating and extending a mirrored volume resource, be sure to exit from any DataKeeper GUI processes that are connected to any of the LifeKeeper for Windows cluster systems.

1. Select the server, and then select Create Resource Hierarchy from the server context menu or server context toolbar.

2. The Create Protected Application window appears displaying the Primary and Backup Servers in your cluster. If not already selected, choose the appropriate systems to configure.

3. A dialog appears with a list of all recognized recovery kits installed within the cluster. When the Back button is active in any of the dialog boxes, you can go back to the previous dialog box. This is especially helpful should you encounter an error that might require you to correct previously entered information. If you click Cancel at any time during the sequence of creating your hierarchy, LifeKeeper for Windows will cancel the entire creation process.

4. After the data is entered, the Next button will appear. When you click Next, LifeKeeper for Windows will create and validate your resource hierarchy.

5. After receiving the message that the resource hierarchy has been created successfully, click Next to continue. The Extend Volume Resource window displays. Refer to the help topic, Extending a Volume Resource Hierarchy for additional information while completing this procedure.

6. If LifeKeeper for Windows has detected a problem, an ERROR will appear in the information box, the partially created resource hierarchy will be removed and the Next button will be disabled. In that case, click Cancel to exit the Wizard.

After the Volume Resource is Created

After a LifeKeeper for Windows volume is created or deleted, the following command is executed for the LifeKeeper for Windows protected volume:

chkntfs /x <vol_1> <vol_2> … <vol_n>

This Windows command excludes the volumes listed from being checked by chkdsk at system startup. This is required for LifeKeeper for Windows protected volumes so that they will not be accessed – particularly on backup systems – before LifeKeeper has a chance to start. If no LifeKeeper for Windows volumes remain, chkntfs /d is executed to restore the Windows default settings.

!The chkntfs /x command does not remember previous volumes it was applied to, so if a user executes this command, it could disable the LifeKeeper for Windows settings, (and likewise, LifeKeeper for Windows could subsequently override the user’s settings). If you wish to exclude a non-LifeKeeper for Windows volume from checking at startup, you should also include all the LifeKeeper for Windows volumes in the chkntfs /x command.