Linux Archive

Linux Archive (http://www.linux-archive.org/)
-   CentOS Docs (http://www.linux-archive.org/centos-docs/)
-   -   Updating the "RAID1 HowTo" to CentOS 6 (http://www.linux-archive.org/centos-docs/662285-updating-raid1-howto-centos-6-a.html)

Gianni Giardina 05-02-2012 03:47 PM

Updating the "RAID1 HowTo" to CentOS 6
 
Hi.

The following HowTo on the CentOS Wiki:

http://wiki.centos.org/HowTos/Install_On_Partitionable_RAID1

valid for CentOS 5, has not been updated to CentOS 6, yet. I found it
very useful during the glorious CentOS 5 days and now that I've
successfully ported my RAID1 experience to CentOS 6, I'd like to share
it with the Community.

The title of the HowTo is currently:

"How to install CentOS 5 on a software partitionable RAID1".

After my update it will be"

"How to install CentOS 5 & 6 on a software partitionable RAID1".

Could someone, please, give me the rights to edit that Wiki page?

My user name is: GianniGiardina


Thanks in advance. Regards

Gianni


_______________________________________________
CentOS-docs mailing list
CentOS-docs@centos.org
http://lists.centos.org/mailman/listinfo/centos-docs

Adrian Sevcenco 05-07-2012 06:24 PM

Updating the "RAID1 HowTo" to CentOS 6
 
On 05/02/12 18:47, Gianni Giardina wrote:

Hi.
The following HowTo on the CentOS Wiki:

http://wiki.centos.org/HowTos/Install_On_Partitionable_RAID1

valid for CentOS 5, has not been updated to CentOS 6, yet. I found it
very useful during the glorious CentOS 5 days and now that I've
successfully ported my RAID1 experience to CentOS 6, I'd like to share
it with the Community.


I have a question regarding partionable RAID :
why should the --metadata=0.90 be used?
in my man page (centos 6.2) i have this :
-e, --metadata=
Declare the style of RAID metadata (superblock) to be used. The
default is 1.2 for --create, and to guess for other operations. The
default can be overridden by setting the metadata value for the CREATE
keyword in mdadm.conf.


Options are:

0, 0.90 Use the original 0.90 format superblock. This format limits
arrays to 28 component devices and limits component devices of levels 1
and greater to 2 terabytes. It is also possible for there to be
confusion about whether the superblock applies to a whole device or just
the last partition, if that partition starts on a 64K boundary.


1, 1.0, 1.1, 1.2 default Use the new version-1 format superblock.
This has fewer restrictions. It can easily be moved between hosts with
different endian-ness, and a recovery operation can be checkpointed and
restarted. The different sub-versions store the superblock at different
locations on the device, either at the end (for 1.0), at the start (for
1.1) or 4K from the start (for 1.2). "1" is equivalent to "1.2".
"default" is equivalent to "1.2".


given the existence of 2+ tb hdd, metadata 0.9 is no go from the start
... so, why 0.9 ?


Thanks,
Adrian

_______________________________________________
CentOS mailing list
CentOS@centos.org
http://lists.centos.org/mailman/listinfo/centos

Les Mikesell 05-07-2012 07:41 PM

Updating the "RAID1 HowTo" to CentOS 6
 
On Mon, May 7, 2012 at 1:24 PM, Adrian Sevcenco <Adrian.Sevcenco@cern.ch> wrote:
> On 05/02/12 18:47, Gianni Giardina wrote:
>>
>> Hi.
>> The following HowTo on the CentOS Wiki:
>>
>> http://wiki.centos.org/HowTos/Install_On_Partitionable_RAID1
>>
>> valid for CentOS 5, has not been updated to CentOS 6, yet. I found it
>> very useful during the glorious CentOS 5 days and now that I've
>> successfully ported my RAID1 experience to CentOS 6, I'd like to share
>> it with the Community.
>
>
> I have a question regarding partionable RAID :
> why should the --metadata=0.90 be used?
> in my man page (centos 6.2) i have this :
> -e, --metadata=
> Declare *the *style *of RAID metadata (superblock) to be used. *The default
> is 1.2 for --create, and to guess for other operations. *The default can be
> overridden by setting the metadata value for the CREATE keyword in
> mdadm.conf.
>
> Options are:
>
> 0, 0.90 * *Use the original 0.90 format superblock. *This format limits
> arrays to 28 component devices and limits component devices of levels 1 and
> *greater *to *2 *terabytes. * It *is *also possible for there to be
> confusion about whether the superblock applies to a whole device or just the
> last partition, if that partition starts on a 64K boundary.
>
> 1, 1.0, 1.1, 1.2 default * Use the new version-1 format superblock. This has
> fewer restrictions. *It can easily be moved between hosts with different
> endian-ness, and a recovery operation can be checkpointed and restarted.
> *The different sub-versions store the superblock at different locations on
> the device, either at the end (for 1.0), at the start (for 1.1) or 4K from
> the start (for 1.2). *"1" is equivalent to "1.2". "default" is equivalent to
> "1.2".
>
> given the existence of 2+ tb hdd, metadata 0.9 is no go from the start ...
> so, why 0.9 ?

I always thought it was a huge advantage for software raid that the
kernel would autodetect and assemble the components. Is there a way
to make that happen with 1.x metadata?

--
Les Mikesell
lesmikesell@gmail.com
_______________________________________________
CentOS mailing list
CentOS@centos.org
http://lists.centos.org/mailman/listinfo/centos

Ljubomir Ljubojevic 05-07-2012 08:02 PM

Updating the "RAID1 HowTo" to CentOS 6
 
On 05/07/2012 08:24 PM, Adrian Sevcenco wrote:
> On 05/02/12 18:47, Gianni Giardina wrote:
>> Hi.
>> The following HowTo on the CentOS Wiki:
>>
>> http://wiki.centos.org/HowTos/Install_On_Partitionable_RAID1
>>
<snip>
> given the existence of 2+ tb hdd, metadata 0.9 is no go from the start
> ... so, why 0.9 ?
>

0.90 is needed so older GRUB can boot from that RAID1 partition.


--

Ljubomir Ljubojevic
(Love is in the Air)
PL Computers
Serbia, Europe

Google is the Mother, Google is the Father, and traceroute is your
trusty Spiderman...
StarOS, Mikrotik and CentOS/RHEL/Linux consultant
_______________________________________________
CentOS mailing list
CentOS@centos.org
http://lists.centos.org/mailman/listinfo/centos


All times are GMT. The time now is 07:25 PM.

VBulletin, Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Content Relevant URLs by vBSEO ©2007, Crawlability, Inc.