ASM and disk partitions offset

From: Radoulov, Dimitre <>
Date: Mon, 13 Feb 2012 23:31:58 +0100
Message-ID: <>

Hi all,
target environment: RAC on RHEL 5.7 x86-64
SAN HP 3PAR I'm reading the following note on MOS: RAC and Oracle Clusterware Best Practices and Starter Kit (Linux) [ID 811306.1], in the attached document RACGuides_Rac11gR2OnLinux.pdf is a step by step description of the GI and RAC installation process.

Does anyone know what's the reason for the requirement for 1 MB offset for the first sector
and if this requirement is valid on certain types of storage only?

3.1.1. Partition the Shared Disks:

  1. Once the LUNs have been presented from the SAN to ALL servers in the cluster, partition the LUNs from one node only, run fdisk to create a single whole-disk partition with exactly 1 MB offset on each LUN to be used as ASM Disk.


Received on Mon Feb 13 2012 - 16:31:58 CST

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