Re: Please help with a special RAID 1 setup

On Jan 7, 12:16pm, Mircea Ciocan wrote:
} Subject: Please help with a special RAID 1 setup

    Hello all,

Good morning to everyone on the list(s).

    First excuse me for a looong message, but I've tryed to give as much 
relevant details as possible.

    Please help me with this weird setup if it is possible and fesable:

    I have this raid1 device, composed of two fibre channel devices 
mounted in RAID1, it works absolutely flawlessly.
The resulted device is used for a lot of important data logging and the 
ideea is to hotattach a 3-rd device ot the same size, wait for 
syncronisation and after all of them are syncronised, stop the data 
logging process, wait for a while, issue a sync command and hot detach 
the 3-rd device restart de data logging and walk away with valid 
filesytem backup of the main arry to be used as separate data analysys 
source. I know that solution is somewhat cumberome but trust me this is 
needed as is.

I know that it adds complexity but it would seem that this solution
would benefit from using LVM with its snap-shotting capabilities.

If you need to walk away with the data, snap the filesystem, copy the
snap to a separate device/filesystem, release the snap and you are
done.  I believe that there is a utility floating around that will
force synchronization of the filesystem (ext[23]) if your desire is to
have a coherent filesystem image as well.

I suspect that in the long run you will have a more coherent log image
with less muss and fuss.

       Mircea Ciocan

Good luck with the project.

}-- End of excerpt from Mircea Ciocan

As always,
Dr. G.W. Wettstein, Ph.D.   Enjellic Systems Development, LLC.
4206 N. 19th Ave.           Specializing in information infra-structure
Fargo, ND  58102            development.
PH: 701-281-1686
FAX: 701-281-3949           EMAIL: greg@enjellic.com
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