[Pvfs2-users] Question about redundancy

[Rob Ross]

Hi Steve,

We get this question a lot.

Software redundancy in a parallel file system is a very challenging 
problem, particularly to provide efficient access at the same time.

The group at Clemson has been looking into this as a research project, 
and I believe that others have as well. If a group creates a solution 
that performs well, reliably operates, and fits into the rest of the 
PVFS system, then we would certainly consider integrating it into the 
production releases. This hasn't happened so far...

Regards,

Rob

Steve wrote:
> Is built in redundancy planned ? Or not in the scope of the project ?
> 
> Steve
> 
> Trusting my 1.1Tb to the reliability of my drives, and touch wood in 20
> years of computing had never had a drive fail. Now ive just put a curse on
> them!
>  
> -------Original Message------- 
>  
> From: Robert Latham 
> Date: 24/04/2007 14:14:13 
> To: Erich Weiler 
> Cc: pvfs2-users at beowulf-underground.org 
> Subject: Re: [Pvfs2-users] Question about redundancy 
>  
> On Mon, Apr 23, 2007 at 05:03:39PM -0700, Erich Weiler wrote: 
>> I need to be clear on this before putting a lot of time into it, but it 
>> sounds like this might be a good solution for our firm, as we have a 200 
>> node cluster each with one 500GB disk, 400GB of which can be leveraged 
>> to a massive parallel file system (400GB x 200 nodes = one big ~80TB 
>> distributed file system). But that assumes that there is no redundancy, 
>> other wise that 80TB would be more like 50-60TB max or something because 
>> there would be some redundancy in there... ? 
>  
> Murali's explanation is spot-on: no software-based reduncancy scheme. 
>  
> For users concerned with redundancy, we suggest hardware failover to 
> Shared storage, which works quite well. 
>  
> ==rob 
>