LVM Recovery Kit Notes and Restrictions

The following notes and restrictions apply to this version of the LVM Recovery Kit.

Support for Raw I/O and Entire Disks

While Figure 1 shows logical volumes residing below various file systems and volume groups on top of disk partitions, it is important to note that the LVM Recovery Kit can support raw access to logical volumes when used in conjunction with the LifeKeeper Raw I/O Recovery Kit and can manage volume groups that are composed of one or more entire disks (e.g./dev/sdc) rather than disk partitions (e.g./dev/sdc1)

Also see the section Using LVM with DataKeeper for a further option in the use of LVM.

Volume Group Activation

In the current LVM implementations, when a volume group is activated, all logical volumes associated with that volume group are also activated automatically. For LifeKeeper, this means that there will be times when a logical volume is active despite the fact that its associated resource instance is still marked as being Out-of-Service (OSU). In a typical failover or switchover operation, LifeKeeper will attempt to bring the logical volumes in service immediately after the volume groups anyway, and the resulting calls to the restore script will return immediately with a success indication. This unneeded attempt to bring the logical volumes in service has no usability impact.

LVM mirroring functionality is not supported

The logical volume subsystem within the Linux OS (LVM) has a mirror feature. This feature is not supported by the LVM Recovery Kit.