Chapter 3. LVM Administration Overview
3.1. Creating LVM Volumes in a Cluster
To create logical volumes in a cluster environment, you use the Clustered Logical Volume Manager (CLVM), which is a set of clustering extensions to LVM. These extensions allow a cluster of computers to manage shared storage (for example, on a SAN) using LVM. In order to use CLVM, the High Availability Add-On and Resilient Storage Add-On software, including the
daemon, must be started at boot time, as described in Section 1.4, “The Clustered Logical Volume Manager (CLVM)”
Creating LVM logical volumes in a cluster environment is identical to creating LVM logical volumes on a single node. There is no difference in the LVM commands themselves, or in the LVM GUI interface. In order to enable the LVM volumes you are creating in a cluster, the cluster infrastructure must be running and the cluster must be quorate.
CLVM requires changes to the
file for cluster-wide locking. Information on configuring the
file to support clustered locking is provided within the
file itself. For information about the
file, see Appendix B, The LVM Configuration Files
When you create volume groups with CLVM on shared storage, you must ensure that all nodes in the cluster have access to the physical volumes that constitute the volume group. Asymmetric cluster configurations in which some nodes have access to the storage and others do not are not supported.
For information on how to install the High Availabily Add-On and set up the cluster infrastructure, see Cluster Administration.