Re: ASM and disk partitions offset

  • From: "Radoulov, Dimitre" <cichomitiko@xxxxxxxxx>
  • To: Riyaj Shamsudeen <riyaj.shamsudeen@xxxxxxxxx>
  • 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.
Hi Riyaj,
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 
offset.
This requirement is documented in the Install guide for Solaris:


         Oracle Solaris fdisk partitions must start at cylinder 1, not 
cylinder 0.



Best regards
Dimitre

> Cheers
>
> 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 
> <http://tinyurl.com/book-expert-plsql-practices>
>
>
>
>
> On Mon, Feb 13, 2012 at 4:31 PM, Radoulov, Dimitre 
> <cichomitiko@xxxxxxxxx <mailto:cichomitiko@xxxxxxxxx>> wrote:
>
>     Hi all,
>     target environment:
>
>     11.2.0.3 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.
>
>
>
>     Thanks
>     Dimitre
>
>
>
>     --
>     //www.freelists.org/webpage/oracle-l
>
>
>



--
//www.freelists.org/webpage/oracle-l


Other related posts: