You can definitely move the disks around in a Windows software mirror.
I Had to do it the other day after a disk failed.  I have never had disk
signature issues like you describe except on clusters (and those are not
really a big problem on 32 bit Windows b/c of dumpcfg).  Easily fixable
arc path problems, yes.

 

All that said, I never do anything like this without a verified disk
image taken of the good disk when the OS is not running.  (Using a
bootable image making CD, for example, or even pulling the disk and
putting it in a different machine.)

 

From: Bill Songstad [mailto:[email protected]] 
Sent: Thursday, October 08, 2009 12:01 PM
To: NT System Admin Issues
Subject: Re: Once more - software RAID

 

A software mirror creates a mirror and that will protect you from a
single disk failure.  That is a certainly better than nothing at all if
redundancy is your goal.  

 

A couple of things to keep in mind though, a windows software mirror
will have a read/wite performance cost that you might notice if you are
doing huge file copies or disk to disk backups to that drive.  Too much
activity, and the write operations could trip.  That can cause a system
crash or file corruption which is worse than nothing at all.  You really
should evaluate your server disk load before deciding on a software
raid.


The worst thing though, in my opinion is the way windows handles disk
signatures in this case.  It is imparative that you never change disk
order in the event of a failed mirror.  If your primary goes down, you
must rebuild the new disk as the primary.  You cannot simply move the
secondary to the primary slot and boot.  Also you cannot take the
secondary out and drop it in identicle hardware and have it boot as a
test machine.  The mirror has to exist, even if broken, in the right
order.

 

All that said, I have one server running software raid, and I want to
change it to hardware raid because it does disk to disk backups and
sometimes they fail on me.  So although I think it is better than
nothing, I still hate it.

 

Bill

On Thu, Oct 8, 2009 at 8:37 AM, <[email protected]> wrote:


Greetings! 

I pulled a PE-850 out of storage to re-build.  It will be running
Windows 2003 SP2.  Its sticker said two SATA drives... 

It turns out it lacks a PERC (Dell RAID controller).  Given that each
disk has more than adequate space for both a system partition and the
data partition (for its intended use), what is the consensus... 

Is the Microsoft "software RAID", to mirror the disks in a quasi RAID1,
better than nothing, the equivalent of nothing, or worse than nothing? 

Thanks!
-- 
Richard D. McClary 
Systems Administrator, Information Technology Group 
  
ASPCA(r) 
1717 S. Philo Rd, Ste 36 
Urbana, IL  61802 
  
[email protected] 
  
P: 217-337-9761 
C: 217-417-1182 
F: 217-337-9761 
www.aspca.org <http://www.aspca.org/>  
  

The information contained in this e-mail, and any attachments hereto, is
from The American Society for the Prevention of Cruelty to Animals(r)
(ASPCA(r)) and is intended only for use by the addressee(s) named herein
and may contain legally privileged and/or confidential information. If
you are not the intended recipient of this e-mail, you are hereby
notified that any dissemination, distribution, copying or use of the
contents of this e-mail, and any attachments hereto, is strictly
prohibited. If you have received this e-mail in error, please
immediately notify me by reply email and permanently delete the original
and any copy of this e-mail and any printout thereof. 
  

 

 

 

 

 

~ Finally, powerful endpoint security that ISN'T a resource hog! ~
~ <http://www.sunbeltsoftware.com/Business/VIPRE-Enterprise/>  ~

Reply via email to