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Re: firewire storage solution recommended

> > > But if question is "can two hosts mount the same 1394 device (in R/W
> > > mode) at the same time ?", the answer is definetly no. At least with
> > > "conventional" FS (ext2/3, fat, etc.), for various reasons,
> > > : kernel level read/write cache, which can assume things about
> > > on the drive and what's not (yet), no locking, etc.
> > >
> Then is there any explanation for the case of SAN? Multiple server use
> fiber to access the same storage device. How come? Any good reference?
> >

Again, most of those SAN solutions have some sort of intelligence (OS)
embedded, like embedded Linux or something, giving it that bit of
intelligence that allows it to do simple things like file locking and
such. I  could be wrong as I've only played with those NAS servers that
use NFS, but afaik thats the way those work. To put it simply, once you
talk about two computers accessing the same storage device at the same
time in read and write, you're going to need SOME sort of intelligence to
prevent them both writing to the same file at the same time and stuffing
things up. Whether that is done on the Filesystem/software level with some
of those new filesystems (i've never had the chance to work with them, so
no comment as to reliability/performance), OR is done in hardware with a
seperate CPU and such (so basically a mini/micro server) that will handle
that task for you.

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