Re: ASM and disk partitions offset
Date: Tue, 14 Feb 2012 00:08:45 +0100
On 14/02/2012 00:00, Riyaj Shamsudeen wrote:
> I don't recollect exact details, but disk VTOC (Volume Table of
> Contents) information is kept in the initial part of the disk, in
> Solaris. You have to skip 1MB, so that VTOC is not overwritten. This
> applies only to Solaris, AFAIK.
thanks for pointing this out.
Yes, now I remember that I wasn't able to make the partitions visible
for asm disk creation until I partitioned the disks using a non-default
This requirement is documented in the Install guide for Solaris:
Oracle Solaris fdisk partitions must start at cylinder 1, not cylinder 0.
> Riyaj Shamsudeen
> Principal DBA,
> Ora!nternals - http://www.orainternals.com - Specialists in
> Performance, RAC and EBS
> Blog: http://orainternals.wordpress.com
> OakTable member http://www.oaktable.com and Oracle ACE Director
> Co-author of the books: Expert Oracle Practices
> <http://tinyurl.com/book-expert-oracle-practices/>, Pro Oracle
> SQL,Expert PL/SQL Practices
> On Mon, Feb 13, 2012 at 4:31 PM, Radoulov, Dimitre
> <cichomitiko_at_gmail.com <mailto:cichomitiko_at_gmail.com>> wrote:
> Hi all,
> target environment:
> 18.104.22.168 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.