[Building Sakai] Creating Mirrors of files

[Hedrick Charles]

What are you trying to protect against?

I assume most of us do a couple of levels of protection. Start with RAID. Most operating systems have support built into the operating system in the file manager. We need to know which operating system you're using to give advice. RAID will protect against failure of a single disk drive, and in some configurations, more than one. If you are very careful it can also protect against failure of a disk controller. However all of your disks will be online on a single system, so in theory a software failure could still lose the whole thing. So could a typo by an operator, and to be honest that's more common these days than hardware failure. (I have lost a couple of different RAIDed systems due to operator error, one arguably my own.)

If you want to protect against that you need to separate copies of the file system on two systems, possibly in two locations. There are technologies that can do that, but again they depend upon your operating system. And this may not be easy to set up and manage. Be aware that if you keep two exact copies and they synchronize in real time, some software failures and operator errors will simply propagate to the backup, so this isn't a replacement for disaster recovery backups.



On Nov 1, 2010, at 7:27:10 AM, Shoaib Chaudhary wrote:

> Hello, 
> 
> Can you please guide me about RAID I haven't use it before
> 
> Many Thanks 
> 
> On Mon, Nov 1, 2010 at 16:18, Steve Swinsburg <steve.swinsburg at gmail.com> wrote:
> Hi,
> 
> In that case you want to use RAID on your filesystem.
> 
> cheers,
> Steve
> 
> 
> 
> On 01/11/2010, at 10:10 PM, Shoaib Chaudhary wrote:
> 
>> Hi Steve, 
>> 
>> No, actually i want a mirror based file storing at two different locations of my hard drive or two different hard drives so that in case of if HDD crash I can recover data from other location. 
>> 
>> On Mon, Nov 1, 2010 at 13:47, Steve Swinsburg <steve.swinsburg at gmail.com> wrote:
>> Hi,
>> 
>> You could store that file in a central spot and make it public and then just link it in the other sites. Or automate that via the web services or similar.
>> 
>> cheers,
>> Steve
>> 
>> On 01/11/2010, at 6:43 PM, Shoaib Chaudhary wrote:
>> 
>>> Hello,
>>> 
>>> Is there any configurations in sakai.properties file that create a mirror of file?
>>> I mean that file A get stored to path A and B simultaneosly.
>>> 
>>> -- 
>>> Regards 
>>> MUHAMMAD SHOAIB | Software Engineer  
>>> 
>>> _______________________________________________
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>> 
>> 
>> 
>> 
>> -- 
>> Regards 
>> MUHAMMAD SHOAIB | Software Engineer  
>> National University of Computer and Emerging Sciences
>> A. K. Brohi Road (Near Police Line) H11/4 Islamabad 
>> Tel +92-(51)-111-128-128 Ext 344  Cell +92-(331)-544213
>> muhammad.shoaib at nu.edu.pk 
>> 
>> As a muslim I have no duty to allow myself to be cheated, but I have the duty to be a fighter for 
>> truth and justice as It is always more difficult to fight against faith than against knowledge
>> 
>> No part of this email and its attached contents should be reproduced,
>> published in any form by any means, electronic or mechanical including
>> photocopy or any information storage or retrieval system nor should the
>> material be disclosed to third parties
>> 
> 
> 
> 
> 
> -- 
> Regards 
> MUHAMMAD SHOAIB | Software Engineer  
> National University of Computer and Emerging Sciences
> A. K. Brohi Road (Near Police Line) H11/4 Islamabad 
> Tel +92-(51)-111-128-128 Ext 344  Cell +92-(331)-544213
> muhammad.shoaib at nu.edu.pk 
> 
> As a muslim I have no duty to allow myself to be cheated, but I have the duty to be a fighter for 
> truth and justice as It is always more difficult to fight against faith than against knowledge
> 
> No part of this email and its attached contents should be reproduced,
> published in any form by any means, electronic or mechanical including
> photocopy or any information storage or retrieval system nor should the
> material be disclosed to third parties
> 
> _______________________________________________
> sakai-dev mailing list
> sakai-dev at collab.sakaiproject.org
> http://collab.sakaiproject.org/mailman/listinfo/sakai-dev
> 
> TO UNSUBSCRIBE: send email to sakai-dev-unsubscribe at collab.sakaiproject.org with a subject of "unsubscribe"

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