Re: [CentOS] Expanding RAID 10 array, WAS: 40TB File System Recommendations

2011-04-15 Thread Christopher Chan
On Thursday, April 14, 2011 11:19 PM, Ray Van Dolson wrote:
 On Thu, Apr 14, 2011 at 10:44:00PM +0800, Christopher Chan wrote:
 On Thursday, April 14, 2011 10:11 PM, Ray Van Dolson wrote:
 On Thu, Apr 14, 2011 at 10:07:55PM +0800, Emmanuel Noobadmin wrote:
 On 4/14/11, John R Piercepie...@hogranch.com   wrote:
 since this is the centos list, I really didn't want to suggest this, but
 if I was building a 20 or 40TB or whatever storage server, I do believe
 I'd be strongly consider using Solaris, or one of its variants like
 OpenIndiana, with ZFS.

 ZFS was engineered from the ground up to scale to zetabytes

 I was actually considering this but then came news that Oracle was
 killing OpenSolaris and likely to be pushing OCFS so decided I
 probably don't want to have something come bite me a year or two down
 the road. I'm not sure how things developed since then though.

 But based on your recommendation and Christopher Chan's, it would seem
 like you guys don't think that long term support/updates would be an
 issue for ZFS?

 ZFS and OCFS play in different spaces.  And ZFS is going nowhere... if
 you want to use on an open OS, OpenIndiana may be a good bet, but
 you're best short-term / mature option would be Nexenta or Solaris
 Express.


 Huh? What gives Nexenta a better advantage over OpenIndiana? They are
 both in the same boat. Both will have to migrate to illumos and move
 away from the last OpenSolaris ON release. Oh, Nexenta has a company
 backing it? Makes no different when both projects will be using the same
 core image. Now, if OpenIndiana resists using illumos, then you will
 have a case for Nexenta over OpenIndiana.

 OpenIndiana is in their what, first release?  I don't think that
 Nexenta 3.x is based on it *yet*.

 Both will eventually converge.

 In the meantime, yes, for storage needs I'd go with Nexenta for the
 reasons you mentioned. :)

Hardy userland, gcc compiled and gnu linked...hmm...I'll give Nexenta a 
shot after they start basing on perhaps Lucid repos.



 For personal use?  Maybe different factors.

 Nexenta the company of course will be contributing to OpenIndiana and
 Illumos...


Now that is news to me. I know that Garrett would be willing to spare a 
man IF the OpenIndiana guys start using illumos as their base for the 
next release...
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Re: [CentOS] Expanding RAID 10 array, WAS: 40TB File System Recommendations

2011-04-15 Thread Christopher Chan
On Friday, April 15, 2011 02:46 AM, John R Pierce wrote:
 On 04/14/11 7:44 AM, Christopher Chan wrote:
 Now, if OpenIndiana resists using illumos...

 openindiana is under the Illumos project umbrella.  They aren't going to
 use anything else.

Eh? I was under the impression that they are separate and that Garrett 
Damore was rather unhappy with the initial direction of OpenIndiana in 
not preparing for an illumos release. 148 is still not illumos as far as 
I know.
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Re: [CentOS] Expanding RAID 10 array, WAS: 40TB File System Recommendations

2011-04-15 Thread John R Pierce
On 04/14/11 5:43 PM, Christopher Chan wrote:
 On Friday, April 15, 2011 02:46 AM, John R Pierce wrote:
 On 04/14/11 7:44 AM, Christopher Chan wrote:
 Now, if OpenIndiana resists using illumos...
 openindiana is under the Illumos project umbrella.  They aren't going to
 use anything else.
 Eh? I was under the impression that they are separate and that Garrett
 Damore was rather unhappy with the initial direction of OpenIndiana in
 not preparing for an illumos release. 148 is still not illumos as far as
 I know.

afaik, both are still using pretty much the last opensolaris kernel with 
minor changes


I was going on this, which says OpenIndiana is a member of the Illumos 
Foundation, that Illumos was providing the core/kernel, and OpenIndiana 
is integrating it into a complete system aka distribution
http://wiki.openindiana.org/oi/Frequently+Asked+Questions#FrequentlyAskedQuestions-WhatistherelationshipbetweenOpenIndianaandIllumos%3F

They go onto say they are waiting for Illumos to mature before they 
integrate it.
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Re: [CentOS] Expanding RAID 10 array, WAS: 40TB File System Recommendations

2011-04-15 Thread Ljubomir Ljubojevic
John R Pierce wrote:
 On 04/14/11 5:43 PM, Christopher Chan wrote:
 On Friday, April 15, 2011 02:46 AM, John R Pierce wrote:
 On 04/14/11 7:44 AM, Christopher Chan wrote:
 Now, if OpenIndiana resists using illumos...
 openindiana is under the Illumos project umbrella.  They aren't going to
 use anything else.
 Eh? I was under the impression that they are separate and that Garrett
 Damore was rather unhappy with the initial direction of OpenIndiana in
 not preparing for an illumos release. 148 is still not illumos as far as
 I know.
 
 afaik, both are still using pretty much the last opensolaris kernel with 
 minor changes
 
 
 I was going on this, which says OpenIndiana is a member of the Illumos 
 Foundation, that Illumos was providing the core/kernel, and OpenIndiana 
 is integrating it into a complete system aka distribution
 http://wiki.openindiana.org/oi/Frequently+Asked+Questions#FrequentlyAskedQuestions-WhatistherelationshipbetweenOpenIndianaandIllumos%3F
 
 They go onto say they are waiting for Illumos to mature before they 
 integrate it.

Eham..., CentOS mailinglist maybe to continue in private?

Ljubomir
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Re: [CentOS] Expanding RAID 10 array, WAS: 40TB File System Recommendations

2011-04-15 Thread Rudi Ahlers
On Fri, Apr 15, 2011 at 10:40 AM, Ljubomir Ljubojevic off...@plnet.rswrote:

 John R Pierce wrote:
  On 04/14/11 5:43 PM, Christopher Chan wrote:
  On Friday, April 15, 2011 02:46 AM, John R Pierce wrote:
  On 04/14/11 7:44 AM, Christopher Chan wrote:
  Now, if OpenIndiana resists using illumos...
  openindiana is under the Illumos project umbrella.  They aren't going
 to
  use anything else.
  Eh? I was under the impression that they are separate and that Garrett
  Damore was rather unhappy with the initial direction of OpenIndiana in
  not preparing for an illumos release. 148 is still not illumos as far as
  I know.
 
  afaik, both are still using pretty much the last opensolaris kernel with
  minor changes
 
 
  I was going on this, which says OpenIndiana is a member of the Illumos
  Foundation, that Illumos was providing the core/kernel, and OpenIndiana
  is integrating it into a complete system aka distribution
 
 http://wiki.openindiana.org/oi/Frequently+Asked+Questions#FrequentlyAskedQuestions-WhatistherelationshipbetweenOpenIndianaandIllumos%3F
 
  They go onto say they are waiting for Illumos to mature before they
  integrate it.

 Eham..., CentOS mailinglist maybe to continue in private?

 Ljubomir



Eham., many people are learning a lot more from this thread than a lot
of the other threads in the past few days. let them continue, and don't
subscribe to the tread :)


-- 
Kind Regards
Rudi Ahlers
SoftDux

Website: http://www.SoftDux.com
Technical Blog: http://Blog.SoftDux.com
Office: 087 805 9573
Cell: 082 554 7532
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Re: [CentOS] Expanding RAID 10 array, WAS: 40TB File System Recommendations

2011-04-15 Thread Christopher Chan
On Friday, April 15, 2011 03:59 PM, John R Pierce wrote:
 On 04/14/11 5:43 PM, Christopher Chan wrote:
 On Friday, April 15, 2011 02:46 AM, John R Pierce wrote:
 On 04/14/11 7:44 AM, Christopher Chan wrote:
 Now, if OpenIndiana resists using illumos...
 openindiana is under the Illumos project umbrella.  They aren't going to
 use anything else.
 Eh? I was under the impression that they are separate and that Garrett
 Damore was rather unhappy with the initial direction of OpenIndiana in
 not preparing for an illumos release. 148 is still not illumos as far as
 I know.

 afaik, both are still using pretty much the last opensolaris kernel with
 minor changes


or nice big changes from the standpoint of those who were pining for 
openindiana with b134+patches



 I was going on this, which says OpenIndiana is a member of the Illumos
 Foundation, that Illumos was providing the core/kernel, and OpenIndiana
 is integrating it into a complete system aka distribution
 http://wiki.openindiana.org/oi/Frequently+Asked+Questions#FrequentlyAskedQuestions-WhatistherelationshipbetweenOpenIndianaandIllumos%3F

oh i see.


 They go onto say they are waiting for Illumos to mature before they
 integrate it.

Yes...like getting g11n in. I guess traction is there already. 
OpenIndiana will be moving to illumos so i guess it would be the one to 
use if one wants a sun cc compiled and sun linked distro.

It's going to be interesting to see how all these different projects 
including CentOS play out.
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Re: [CentOS] Expanding RAID 10 array, WAS: 40TB File System Recommendations

2011-04-15 Thread Ross Walker
On Apr 15, 2011, at 4:48 AM, Rudi Ahlers r...@softdux.com wrote:

 
 
 On Fri, Apr 15, 2011 at 10:40 AM, Ljubomir Ljubojevic off...@plnet.rs wrote:
 John R Pierce wrote:
  On 04/14/11 5:43 PM, Christopher Chan wrote:
  On Friday, April 15, 2011 02:46 AM, John R Pierce wrote:
  On 04/14/11 7:44 AM, Christopher Chan wrote:
  Now, if OpenIndiana resists using illumos...
  openindiana is under the Illumos project umbrella.  They aren't going to
  use anything else.
  Eh? I was under the impression that they are separate and that Garrett
  Damore was rather unhappy with the initial direction of OpenIndiana in
  not preparing for an illumos release. 148 is still not illumos as far as
  I know.
 
  afaik, both are still using pretty much the last opensolaris kernel with
  minor changes
 
 
  I was going on this, which says OpenIndiana is a member of the Illumos
  Foundation, that Illumos was providing the core/kernel, and OpenIndiana
  is integrating it into a complete system aka distribution
  http://wiki.openindiana.org/oi/Frequently+Asked+Questions#FrequentlyAskedQuestions-WhatistherelationshipbetweenOpenIndianaandIllumos%3F
 
  They go onto say they are waiting for Illumos to mature before they
  integrate it.
 
 Eham..., CentOS mailinglist maybe to continue in private?
 
 Ljubomir
 
 
 Eham., many people are learning a lot more from this thread than a lot of 
 the other threads in the past few days. let them continue, and don't 
 subscribe to the tread :)

I agree with both assessments, but since this is a CentOS list and this thread 
has now twisted into ZFS advocacy I must say as well, continue off list.

-Ross

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Re: [CentOS] Expanding RAID 10 array, WAS: 40TB File System Recommendations

2011-04-14 Thread Christopher Chan
On Thursday, April 14, 2011 01:51 PM, John R Pierce wrote:
 On 04/13/11 9:51 PM, Emmanuel Noobadmin wrote:
 I'm was stuck trying to decide whether to go for the cheaper RAID 5
 setup and possibly getting killed by the IOPS penalty and the risk
 associated with rebuild time, or figure out a way to use the
 recommended RAID 10 setup with a smaller usable capacity for the
 budget but do so with the ability to expand in the near future. So
 really hoping that it could be done.

 since this is the centos list, I really didn't want to suggest this, but
 if I was building a 20 or 40TB or whatever storage server, I do believe
 I'd be strongly consider using Solaris, or one of its variants like
 OpenIndiana, with ZFS.

Special cases warrant exemption.

I, too, run OpenIndiana...

Use the right tool for the job.
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Re: [CentOS] Expanding RAID 10 array, WAS: 40TB File System Recommendations

2011-04-14 Thread Emmanuel Noobadmin
On 4/14/11, John R Pierce pie...@hogranch.com wrote:
 since this is the centos list, I really didn't want to suggest this, but
 if I was building a 20 or 40TB or whatever storage server, I do believe
 I'd be strongly consider using Solaris, or one of its variants like
 OpenIndiana, with ZFS.

 ZFS was engineered from the ground up to scale to zetabytes

I was actually considering this but then came news that Oracle was
killing OpenSolaris and likely to be pushing OCFS so decided I
probably don't want to have something come bite me a year or two down
the road. I'm not sure how things developed since then though.

But based on your recommendation and Christopher Chan's, it would seem
like you guys don't think that long term support/updates would be an
issue for ZFS?
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Re: [CentOS] Expanding RAID 10 array, WAS: 40TB File System Recommendations

2011-04-14 Thread Ray Van Dolson
On Thu, Apr 14, 2011 at 10:07:55PM +0800, Emmanuel Noobadmin wrote:
 On 4/14/11, John R Pierce pie...@hogranch.com wrote:
  since this is the centos list, I really didn't want to suggest this, but
  if I was building a 20 or 40TB or whatever storage server, I do believe
  I'd be strongly consider using Solaris, or one of its variants like
  OpenIndiana, with ZFS.
 
  ZFS was engineered from the ground up to scale to zetabytes
 
 I was actually considering this but then came news that Oracle was
 killing OpenSolaris and likely to be pushing OCFS so decided I
 probably don't want to have something come bite me a year or two down
 the road. I'm not sure how things developed since then though.
 
 But based on your recommendation and Christopher Chan's, it would seem
 like you guys don't think that long term support/updates would be an
 issue for ZFS?

ZFS and OCFS play in different spaces.  And ZFS is going nowhere... if
you want to use on an open OS, OpenIndiana may be a good bet, but
you're best short-term / mature option would be Nexenta or Solaris
Express.

Ray
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Re: [CentOS] Expanding RAID 10 array, WAS: 40TB File System Recommendations

2011-04-14 Thread Christopher Chan
On Thursday, April 14, 2011 10:11 PM, Ray Van Dolson wrote:
 On Thu, Apr 14, 2011 at 10:07:55PM +0800, Emmanuel Noobadmin wrote:
 On 4/14/11, John R Piercepie...@hogranch.com  wrote:
 since this is the centos list, I really didn't want to suggest this, but
 if I was building a 20 or 40TB or whatever storage server, I do believe
 I'd be strongly consider using Solaris, or one of its variants like
 OpenIndiana, with ZFS.

 ZFS was engineered from the ground up to scale to zetabytes

 I was actually considering this but then came news that Oracle was
 killing OpenSolaris and likely to be pushing OCFS so decided I
 probably don't want to have something come bite me a year or two down
 the road. I'm not sure how things developed since then though.

 But based on your recommendation and Christopher Chan's, it would seem
 like you guys don't think that long term support/updates would be an
 issue for ZFS?

 ZFS and OCFS play in different spaces.  And ZFS is going nowhere... if
 you want to use on an open OS, OpenIndiana may be a good bet, but
 you're best short-term / mature option would be Nexenta or Solaris
 Express.


Huh? What gives Nexenta a better advantage over OpenIndiana? They are 
both in the same boat. Both will have to migrate to illumos and move 
away from the last OpenSolaris ON release. Oh, Nexenta has a company 
backing it? Makes no different when both projects will be using the same 
core image. Now, if OpenIndiana resists using illumos, then you will 
have a case for Nexenta over OpenIndiana.
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Re: [CentOS] Expanding RAID 10 array, WAS: 40TB File System Recommendations

2011-04-14 Thread Christopher Chan
On Thursday, April 14, 2011 10:07 PM, Emmanuel Noobadmin wrote:
 On 4/14/11, John R Piercepie...@hogranch.com  wrote:
 since this is the centos list, I really didn't want to suggest this, but
 if I was building a 20 or 40TB or whatever storage server, I do believe
 I'd be strongly consider using Solaris, or one of its variants like
 OpenIndiana, with ZFS.

 ZFS was engineered from the ground up to scale to zetabytes

 I was actually considering this but then came news that Oracle was
 killing OpenSolaris and likely to be pushing OCFS so decided I
 probably don't want to have something come bite me a year or two down
 the road. I'm not sure how things developed since then though.

/me is so happy that the Indiana project surfaced.



 But based on your recommendation and Christopher Chan's, it would seem
 like you guys don't think that long term support/updates would be an
 issue for ZFS?

I have found ZFS to be very much stable on OpenSolaris stable releases 
and have not had any issues on OpenIndiana 147 with 9 1TB disks in a 
raidz2 pool. There are reports of those who had problems when upgrading 
but I however have not - whether difference in env/procedure was 
responsible I do not know but those chaps got help on the Openindiana ml 
with their zfs problems.

I have used OpenSolaris since 2008.05 stable release without issues. 
Long term support/updates is not an absolute certainty at the moment 
with regards to OpenIndiana but that is only in the terms of packages 
outside the core image since illumos is guaranteed.
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Re: [CentOS] Expanding RAID 10 array, WAS: 40TB File System Recommendations

2011-04-14 Thread Ray Van Dolson
On Thu, Apr 14, 2011 at 10:44:00PM +0800, Christopher Chan wrote:
 On Thursday, April 14, 2011 10:11 PM, Ray Van Dolson wrote:
  On Thu, Apr 14, 2011 at 10:07:55PM +0800, Emmanuel Noobadmin wrote:
  On 4/14/11, John R Piercepie...@hogranch.com  wrote:
  since this is the centos list, I really didn't want to suggest this, but
  if I was building a 20 or 40TB or whatever storage server, I do believe
  I'd be strongly consider using Solaris, or one of its variants like
  OpenIndiana, with ZFS.
 
  ZFS was engineered from the ground up to scale to zetabytes
 
  I was actually considering this but then came news that Oracle was
  killing OpenSolaris and likely to be pushing OCFS so decided I
  probably don't want to have something come bite me a year or two down
  the road. I'm not sure how things developed since then though.
 
  But based on your recommendation and Christopher Chan's, it would seem
  like you guys don't think that long term support/updates would be an
  issue for ZFS?
 
  ZFS and OCFS play in different spaces.  And ZFS is going nowhere... if
  you want to use on an open OS, OpenIndiana may be a good bet, but
  you're best short-term / mature option would be Nexenta or Solaris
  Express.
 
 
 Huh? What gives Nexenta a better advantage over OpenIndiana? They are 
 both in the same boat. Both will have to migrate to illumos and move 
 away from the last OpenSolaris ON release. Oh, Nexenta has a company 
 backing it? Makes no different when both projects will be using the same 
 core image. Now, if OpenIndiana resists using illumos, then you will 
 have a case for Nexenta over OpenIndiana.

OpenIndiana is in their what, first release?  I don't think that
Nexenta 3.x is based on it *yet*.

Both will eventually converge.

In the meantime, yes, for storage needs I'd go with Nexenta for the
reasons you mentioned. :)

For personal use?  Maybe different factors.

Nexenta the company of course will be contributing to OpenIndiana and
Illumos... 

Ray

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Re: [CentOS] Expanding RAID 10 array, WAS: 40TB File System Recommendations

2011-04-14 Thread John R Pierce
On 04/14/11 7:44 AM, Christopher Chan wrote:
 Now, if OpenIndiana resists using illumos...

openindiana is under the Illumos project umbrella.  They aren't going to 
use anything else.

someone suggested Solaris Express, that has no patches or updates unless 
you subscribe to annual support at several $1000/year/CPU socket.


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Re: [CentOS] Expanding RAID 10 array, WAS: 40TB File System Recommendations

2011-04-13 Thread Ross Walker
On Wed, Apr 13, 2011 at 11:19 AM, Emmanuel Noobadmin
centos.ad...@gmail.com wrote:
 On 4/13/11, Rudi Ahlers r...@softdux.com wrote:
 to expand the array :)

 I haven't had problems doing it this way yet.

 I finally figured out my mistake creating the raid devices and got a
 working RAID 0 on two RAID 1 arrays. But I wasn't able to add another
 RAID 1 component to the array with the error

 mdadm: add new device failed for /dev/md/mdr1_3 as 2: Invalid argument

 Googling up this indicates that it's the expected result trying to add
 a new device to a RAID 0 array. Could you or anybody else please share
 what's the trick to achieving this?

You can't expand a mdraid raid0.

I believe you can expand a mdraid raid10,5,6, but not raid0.

If you want to use separate raid1 devices instead of mdraid's raid10
implementation then use LVM, add them to a VG then stripe the LVs
across the different PVs.

The only problem with that is restriping existing LVs across new PVs
is difficult to the point that it is often better to create new LVs
with the proper striping. You can do it though using 'lvresize' to
change the stripe width, but it won't give a linear striping for
existing data and the LV will eventually fill the first PVs causing
all data to only be written to the last PV.

I often find it handy to have a backup raid1 disk on the system
that's big enough to hold the contents of the largest LV, then dump
the production LV to the backup, blow away the production, recreate
with the new stripe size, then restore the data back. This backup
volume could be an iSCSI volume exported from another server that does
have the capacity if there isn't any in the host.

-Ross
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Re: [CentOS] Expanding RAID 10 array, WAS: 40TB File System Recommendations

2011-04-13 Thread Emmanuel Noobadmin
On 4/14/11, Ross Walker rswwal...@gmail.com wrote:
 You can't expand a mdraid raid0.

 I believe you can expand a mdraid raid10,5,6, but not raid0.

That was what I thought previously when looking into this and weighing
the pros/cons of using RAID 10 vs RAID 5.

But earlier this week, from the 40TB Filesystem thread, Rudi stated
that he has a RAID 0 on RAID 1 setup that he can expand and Brandon
confirmed that it is possible to expand RAID 0.

http://forum.nginx.org/read.php?24,190407,190764#msg-190764

Since I've read that some features such as creating RAID 10 directly
were not in the man pages, and another person in the mdadm list
implied that a raid 10 like array could be achieved using some
creative RAID 5 layout, I assumed that perhaps it was possible to do
that, just that there was some undocumented trick or specific manner
the arrays had to be setup.

I'm was stuck trying to decide whether to go for the cheaper RAID 5
setup and possibly getting killed by the IOPS penalty and the risk
associated with rebuild time, or figure out a way to use the
recommended RAID 10 setup with a smaller usable capacity for the
budget but do so with the ability to expand in the near future. So
really hoping that it could be done.


 I often find it handy to have a backup raid1 disk on the system
 that's big enough to hold the contents of the largest LV, then dump
 the production LV to the backup, blow away the production, recreate
 with the new stripe size, then restore the data back. This backup
 volume could be an iSCSI volume exported from another server that does
 have the capacity if there isn't any in the host.

That sounds like a solution since each LV shouldn't be too massive.
This seems to imply I would have to bring down the service running off
the LV during the recreation but I suppose I since the storage is
planned to be exported over iSCSI in the first place, I could simply
export the backup copy while expanding the original.
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Re: [CentOS] Expanding RAID 10 array, WAS: 40TB File System Recommendations

2011-04-13 Thread John R Pierce
On 04/13/11 9:51 PM, Emmanuel Noobadmin wrote:
 I'm was stuck trying to decide whether to go for the cheaper RAID 5
 setup and possibly getting killed by the IOPS penalty and the risk
 associated with rebuild time, or figure out a way to use the
 recommended RAID 10 setup with a smaller usable capacity for the
 budget but do so with the ability to expand in the near future. So
 really hoping that it could be done.

since this is the centos list, I really didn't want to suggest this, but 
if I was building a 20 or 40TB or whatever storage server, I do believe 
I'd be strongly consider using Solaris, or one of its variants like 
OpenIndiana, with ZFS.

ZFS was engineered from the ground up to scale to zetabytes

# zpool create archive mirror c2t0d0 c2t1d0 mirror c2t2d0 c2t3d0 mirror 
c3t0d0 c3t1d0 mirror c3t2d0 c3t2d0 . spare c?t?d0 c?t?d0

done.  available for use in a few seconds.  default mountpoint is /archive

# zfs create -o mountpoint=/u01 archive/u01
# zfs create -o mountpoint=/u02 archive/u02

creates a couple more filesystems that share the free space, mounted as 
/u01 and /u02

adding more disks?

# zpool add archive mirror c7t0d0 c7t1d0 mirror c7t2d0 c7t3d0


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