Large FOSS filesystems, was Re: [Beowulf] 512 nodes Myrinet cluster Challanges

[Joe Landman]

Michael Will wrote:
> The question is:
> 
> Can you use LVM to do mirroring and striping at the same time, or do you
> need to use
> software raid1 below LVM for that?

I havent tried this recently.


> When having multiple chassis, the risk is that a chassis goes down and
> that part of a striped
> LVM can affect the whole filesystem, going offline and if the drives
> became corrupted for some
> reason, it can have corrupted all of your data. If you used mirroring
> between two physical volumes
> on two enclosures and then stripe across those mirrors, you could
> mitigate that.

I believe thats what I said.  Make stripes across RAID1 mirrors. AKA 
RAID10.  My apologies if I was unclear.

Joe

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