Chapter 5. Creating the Physical and Logical Volumes

Chapter 5. Creating the Physical and Logical Volumes

5.1. Physical_Storage_Allocation
5.2. Initialize and Configure Volumes

Logical volumes, once created and visible to members of the cluster, will appear to RHEL as block device entries. Logical Volumes can optionally appear as rawdevices using the rawdevices service in RHEL. Both block and raw logical volumes will be used to install RAC. Physical and Logical volumes can be initialized and configured using the commandline or the GUI-based system-config-lvm.

5.1. Physical_Storage_Allocation

The storage array was configured to present a series of physical LUNs that will be initialized and configured by CLVM.

  • One 6GB LUN for Shared Oracle Home

  • One 24GB LUN for datafiles and indexes

  • Four 4GB LUNs for Redo logs and Undo tablespaces


The current version of the GUI tool will not prevent the initialization and addition of local physical volumes to cluster volumes. In this sample cluster, all media handled by LVM2 must be on shared storage for Oracle RAC to function. Do not configure any node-local storage from any of the 7 nodes until it is known that this is resolved in subsequent releases of the GUI tool.

For example, /dev/hda is visible to CLVM and it is a local physical device (the boot disk), but remains un-initialized by CLVM. Only initialize the shared storage intended for use with Oracle RAC.

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