[ale] bigger disks under RAID1 with RHL 9 or RHEL4 on DellPowerEdge?

[James P. Kinney III]

And once again, another spike into the box of why software RAID is my
preferred RAID environment. 

Flexibility is worth more than the 1-2% performance hit. A custom built
NAS box with dual PCI-X buss's sporting a pair of high-speed SATA-II
cards can haul some serious data butt.

Swap out the SATA-II for ultra SCSI 320 and appropriate drives and the
data speed doesn't get much better.

On Thu, 2006-09-21 at 10:06 -0400, Jeff Lightner wrote:
> We use Dell with PERC here.
> 
>  
> 
> Note that there are different PERC versions and even OEMs (Adapatec
> and LSI).   Haven?t done what you say in Linux.  Asked the Windows
> guys who have been using them far longer and they?ve never done it
> either. 
> 
>  
> 
> I doubt the growfs/mdadm for software RAID would deal with hardware
> RAID of PERC.
> 
>  
> 
> My guess is it wouldn?t work.  You?d likely be limited to your
> original partition sizes on the hardware RAID device (e.g. /dev/sda)
> which can be seen with fdisk ?l /dev/sda.  It would be interesting to
> try on a test system.   Perhaps it would extend the 4th partition
> automatically (the Win95 ext) and allow you to create additional
> extended partition.   I wouldn?t try it on an existing production
> system unless I had a full backup and was ready to do a reload and
> restore.
> 
>  
> 
>                                    
> ______________________________________________________________________
> From:ale-bounces at ale.org [mailto:ale-bounces at ale.org] On Behalf Of
> Jerry Yu
> Sent: Thursday, September 21, 2006 9:43 AM
> To: Atlanta Linux Enthusiasts
> Subject: Re: [ale] bigger disks under RAID1 with RHL 9 or RHEL4 on
> DellPowerEdge?
> 
> 
>  
> 
> thanks, Danny. I am aware of the growfs util to grow a software raid
> under Linux. do you mean that it and its  cohorts can handle a
> hardware raid the same way?
> 
> On 9/21/06, Danny Cox <DCox at icc.net> wrote:
> 
> Jerry,
> 
> On Wed, 2006-09-20 at 15:45 -0400, Jerry Yu wrote:
> > I am under the impression if I replace a 9G disk under RAID 1
> > (hardware raid by PERC) with a bigger disk, say 146G, the mirroring
> > would still work fine. After it all synced up, I can swap the 
> > remaining 9G disk with yet another 146G. If all this works out, now
> > I'd have a pair of 146G with its top 9G used in the mirror w/o
> > interrupting service.  However, any way I can use the left-over
> > 146-9=137G ?
> 
>         Yes, there's a new on-the-fly RAID resizing/restructuring
> feature in
> the later kernels.  See the Grow mode of mdadm.  You'll also need an
> FS
> that can dynamically grow also.  XFS can, and I'm pretty sure most of 
> the others can too.
> 
>         Do make a backup first, of course (words of bitter
> experience ;-).
> 
> --
> Daniel S. Cox
> Internet Commerce Corporation
> 
> 
> _______________________________________________ 
> Ale mailing list
> Ale at ale.org
> http://www.ale.org/mailman/listinfo/ale
> 
> 
>  
> 
> 
> _______________________________________________
> Ale mailing list
> Ale at ale.org
> http://www.ale.org/mailman/listinfo/ale
-- 
James P. Kinney III          
CEO & Director of Engineering 
Local Net Solutions,LLC        
770-493-8244                    
http://www.localnetsolutions.com

GPG ID: 829C6CA7 James P. Kinney III (M.S. Physics)
<jkinney at localnetsolutions.com>
Fingerprint = 3C9E 6366 54FC A3FE BA4D 0659 6190 ADC3 829C 6CA7
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 189 bytes
Desc: This is a digitally signed message part